| /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- |
| * vim: set ts=8 sts=4 et sw=4 tw=99: |
| * |
| * Copyright (C) 2009 Apple Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. ``AS IS'' AND ANY |
| * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR |
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY |
| * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "YarrJIT.h" |
| |
| #include "assembler/assembler/LinkBuffer.h" |
| #include "Yarr.h" |
| #include "YarrCanonicalizeUCS2.h" |
| |
| #if ENABLE_YARR_JIT |
| |
| using namespace WTF; |
| |
| namespace JSC { namespace Yarr { |
| |
| template<YarrJITCompileMode compileMode> |
| class YarrGenerator : private MacroAssembler { |
| friend void jitCompile(JSGlobalData*, YarrCodeBlock& jitObject, const String& pattern, unsigned& numSubpatterns, const char*& error, bool ignoreCase, bool multiline); |
| |
| #if WTF_CPU_ARM |
| static const RegisterID input = ARMRegisters::r0; |
| static const RegisterID index = ARMRegisters::r1; |
| static const RegisterID length = ARMRegisters::r2; |
| static const RegisterID output = ARMRegisters::r4; |
| |
| static const RegisterID regT0 = ARMRegisters::r5; |
| static const RegisterID regT1 = ARMRegisters::r6; |
| |
| static const RegisterID returnRegister = ARMRegisters::r0; |
| static const RegisterID returnRegister2 = ARMRegisters::r1; |
| #elif WTF_CPU_MIPS |
| static const RegisterID input = MIPSRegisters::a0; |
| static const RegisterID index = MIPSRegisters::a1; |
| static const RegisterID length = MIPSRegisters::a2; |
| static const RegisterID output = MIPSRegisters::a3; |
| |
| static const RegisterID regT0 = MIPSRegisters::t4; |
| static const RegisterID regT1 = MIPSRegisters::t5; |
| |
| static const RegisterID returnRegister = MIPSRegisters::v0; |
| static const RegisterID returnRegister2 = MIPSRegisters::v1; |
| #elif WTF_CPU_SH4 |
| static const RegisterID input = SH4Registers::r4; |
| static const RegisterID index = SH4Registers::r5; |
| static const RegisterID length = SH4Registers::r6; |
| static const RegisterID output = SH4Registers::r7; |
| |
| static const RegisterID regT0 = SH4Registers::r0; |
| static const RegisterID regT1 = SH4Registers::r1; |
| |
| static const RegisterID returnRegister = SH4Registers::r0; |
| static const RegisterID returnRegister2 = SH4Registers::r1; |
| #elif WTF_CPU_SPARC |
| static const RegisterID input = SparcRegisters::i0; |
| static const RegisterID index = SparcRegisters::i1; |
| static const RegisterID length = SparcRegisters::i2; |
| static const RegisterID output = SparcRegisters::i3; |
| |
| static const RegisterID regT0 = SparcRegisters::i4; |
| static const RegisterID regT1 = SparcRegisters::i5; |
| |
| static const RegisterID returnRegister = SparcRegisters::i0; |
| #elif WTF_CPU_X86 |
| static const RegisterID input = X86Registers::eax; |
| static const RegisterID index = X86Registers::edx; |
| static const RegisterID length = X86Registers::ecx; |
| static const RegisterID output = X86Registers::edi; |
| |
| static const RegisterID regT0 = X86Registers::ebx; |
| static const RegisterID regT1 = X86Registers::esi; |
| |
| static const RegisterID returnRegister = X86Registers::eax; |
| static const RegisterID returnRegister2 = X86Registers::edx; |
| #elif WTF_CPU_X86_64 |
| # if WTF_PLATFORM_WIN |
| static const RegisterID input = X86Registers::ecx; |
| static const RegisterID index = X86Registers::edx; |
| static const RegisterID length = X86Registers::r8; |
| static const RegisterID output = X86Registers::r9; |
| # else |
| static const RegisterID input = X86Registers::edi; |
| static const RegisterID index = X86Registers::esi; |
| static const RegisterID length = X86Registers::edx; |
| static const RegisterID output = X86Registers::ecx; |
| # endif |
| |
| static const RegisterID regT0 = X86Registers::eax; |
| static const RegisterID regT1 = X86Registers::ebx; |
| |
| static const RegisterID returnRegister = X86Registers::eax; |
| |
| # if !WTF_PLATFORM_WIN |
| // no way to use int128_t as return value on Win64 ABI |
| static const RegisterID returnRegister2 = X86Registers::edx; |
| # endif |
| #endif |
| |
| void optimizeAlternative(PatternAlternative* alternative) |
| { |
| if (!alternative->m_terms.size()) |
| return; |
| |
| for (unsigned i = 0; i < alternative->m_terms.size() - 1; ++i) { |
| PatternTerm& term = alternative->m_terms[i]; |
| PatternTerm& nextTerm = alternative->m_terms[i + 1]; |
| |
| if ((term.type == PatternTerm::TypeCharacterClass) |
| && (term.quantityType == QuantifierFixedCount) |
| && (nextTerm.type == PatternTerm::TypePatternCharacter) |
| && (nextTerm.quantityType == QuantifierFixedCount)) { |
| PatternTerm termCopy = term; |
| alternative->m_terms[i] = nextTerm; |
| alternative->m_terms[i + 1] = termCopy; |
| } |
| } |
| } |
| |
| void matchCharacterClassRange(RegisterID character, JumpList& failures, JumpList& matchDest, const CharacterRange* ranges, unsigned count, unsigned* matchIndex, const UChar* matches, unsigned matchCount) |
| { |
| do { |
| // pick which range we're going to generate |
| int which = count >> 1; |
| char lo = ranges[which].begin; |
| char hi = ranges[which].end; |
| |
| // check if there are any ranges or matches below lo. If not, just jl to failure - |
| // if there is anything else to check, check that first, if it falls through jmp to failure. |
| if ((*matchIndex < matchCount) && (matches[*matchIndex] < lo)) { |
| Jump loOrAbove = branch32(GreaterThanOrEqual, character, Imm32((unsigned short)lo)); |
| |
| // generate code for all ranges before this one |
| if (which) |
| matchCharacterClassRange(character, failures, matchDest, ranges, which, matchIndex, matches, matchCount); |
| |
| while ((*matchIndex < matchCount) && (matches[*matchIndex] < lo)) { |
| matchDest.append(branch32(Equal, character, Imm32((unsigned short)matches[*matchIndex]))); |
| ++*matchIndex; |
| } |
| failures.append(jump()); |
| |
| loOrAbove.link(this); |
| } else if (which) { |
| Jump loOrAbove = branch32(GreaterThanOrEqual, character, Imm32((unsigned short)lo)); |
| |
| matchCharacterClassRange(character, failures, matchDest, ranges, which, matchIndex, matches, matchCount); |
| failures.append(jump()); |
| |
| loOrAbove.link(this); |
| } else |
| failures.append(branch32(LessThan, character, Imm32((unsigned short)lo))); |
| |
| while ((*matchIndex < matchCount) && (matches[*matchIndex] <= hi)) |
| ++*matchIndex; |
| |
| matchDest.append(branch32(LessThanOrEqual, character, Imm32((unsigned short)hi))); |
| // fall through to here, the value is above hi. |
| |
| // shuffle along & loop around if there are any more matches to handle. |
| unsigned next = which + 1; |
| ranges += next; |
| count -= next; |
| } while (count); |
| } |
| |
| void matchCharacterClass(RegisterID character, JumpList& matchDest, const CharacterClass* charClass) |
| { |
| if (charClass->m_table) { |
| ExtendedAddress tableEntry(character, reinterpret_cast<intptr_t>(charClass->m_table->m_table)); |
| matchDest.append(branchTest8(charClass->m_table->m_inverted ? Zero : NonZero, tableEntry)); |
| return; |
| } |
| Jump unicodeFail; |
| if (charClass->m_matchesUnicode.size() || charClass->m_rangesUnicode.size()) { |
| Jump isAscii = branch32(LessThanOrEqual, character, TrustedImm32(0x7f)); |
| |
| if (charClass->m_matchesUnicode.size()) { |
| for (unsigned i = 0; i < charClass->m_matchesUnicode.size(); ++i) { |
| UChar ch = charClass->m_matchesUnicode[i]; |
| matchDest.append(branch32(Equal, character, Imm32(ch))); |
| } |
| } |
| |
| if (charClass->m_rangesUnicode.size()) { |
| for (unsigned i = 0; i < charClass->m_rangesUnicode.size(); ++i) { |
| UChar lo = charClass->m_rangesUnicode[i].begin; |
| UChar hi = charClass->m_rangesUnicode[i].end; |
| |
| Jump below = branch32(LessThan, character, Imm32(lo)); |
| matchDest.append(branch32(LessThanOrEqual, character, Imm32(hi))); |
| below.link(this); |
| } |
| } |
| |
| unicodeFail = jump(); |
| isAscii.link(this); |
| } |
| |
| if (charClass->m_ranges.size()) { |
| unsigned matchIndex = 0; |
| JumpList failures; |
| matchCharacterClassRange(character, failures, matchDest, charClass->m_ranges.begin(), charClass->m_ranges.size(), &matchIndex, charClass->m_matches.begin(), charClass->m_matches.size()); |
| while (matchIndex < charClass->m_matches.size()) |
| matchDest.append(branch32(Equal, character, Imm32((unsigned short)charClass->m_matches[matchIndex++]))); |
| |
| failures.link(this); |
| } else if (charClass->m_matches.size()) { |
| // optimization: gather 'a','A' etc back together, can mask & test once. |
| Vector<char> matchesAZaz; |
| |
| for (unsigned i = 0; i < charClass->m_matches.size(); ++i) { |
| char ch = charClass->m_matches[i]; |
| if (m_pattern.m_ignoreCase) { |
| if (isASCIILower(ch)) { |
| matchesAZaz.append(ch); |
| continue; |
| } |
| if (isASCIIUpper(ch)) |
| continue; |
| } |
| matchDest.append(branch32(Equal, character, Imm32((unsigned short)ch))); |
| } |
| |
| if (unsigned countAZaz = matchesAZaz.size()) { |
| or32(TrustedImm32(32), character); |
| for (unsigned i = 0; i < countAZaz; ++i) |
| matchDest.append(branch32(Equal, character, TrustedImm32(matchesAZaz[i]))); |
| } |
| } |
| |
| if (charClass->m_matchesUnicode.size() || charClass->m_rangesUnicode.size()) |
| unicodeFail.link(this); |
| } |
| |
| // Jumps if input not available; will have (incorrectly) incremented already! |
| Jump jumpIfNoAvailableInput(unsigned countToCheck = 0) |
| { |
| if (countToCheck) |
| add32(Imm32(countToCheck), index); |
| return branch32(Above, index, length); |
| } |
| |
| Jump jumpIfAvailableInput(unsigned countToCheck) |
| { |
| add32(Imm32(countToCheck), index); |
| return branch32(BelowOrEqual, index, length); |
| } |
| |
| Jump checkInput() |
| { |
| return branch32(BelowOrEqual, index, length); |
| } |
| |
| Jump atEndOfInput() |
| { |
| return branch32(Equal, index, length); |
| } |
| |
| Jump notAtEndOfInput() |
| { |
| return branch32(NotEqual, index, length); |
| } |
| |
| Jump jumpIfCharNotEquals(UChar ch, int inputPosition, RegisterID character) |
| { |
| readCharacter(inputPosition, character); |
| |
| // For case-insesitive compares, non-ascii characters that have different |
| // upper & lower case representations are converted to a character class. |
| ASSERT(!m_pattern.m_ignoreCase || isASCIIAlpha(ch) || isCanonicallyUnique(ch)); |
| if (m_pattern.m_ignoreCase && isASCIIAlpha(ch)) { |
| or32(TrustedImm32(0x20), character); |
| ch |= 0x20; |
| } |
| |
| return branch32(NotEqual, character, Imm32(ch)); |
| } |
| |
| void readCharacter(int inputPosition, RegisterID reg) |
| { |
| if (m_charSize == Char8) |
| load8(BaseIndex(input, index, TimesOne, inputPosition * sizeof(char)), reg); |
| else |
| load16(BaseIndex(input, index, TimesTwo, inputPosition * sizeof(UChar)), reg); |
| } |
| |
| void storeToFrame(RegisterID reg, unsigned frameLocation) |
| { |
| poke(reg, frameLocation); |
| } |
| |
| void storeToFrame(TrustedImm32 imm, unsigned frameLocation) |
| { |
| poke(imm, frameLocation); |
| } |
| |
| DataLabelPtr storeToFrameWithPatch(unsigned frameLocation) |
| { |
| return storePtrWithPatch(TrustedImmPtr(0), Address(stackPointerRegister, frameLocation * sizeof(void*))); |
| } |
| |
| void loadFromFrame(unsigned frameLocation, RegisterID reg) |
| { |
| peek(reg, frameLocation); |
| } |
| |
| void loadFromFrameAndJump(unsigned frameLocation) |
| { |
| jump(Address(stackPointerRegister, frameLocation * sizeof(void*))); |
| } |
| |
| void initCallFrame() |
| { |
| unsigned callFrameSize = m_pattern.m_body->m_callFrameSize; |
| if (callFrameSize) |
| subPtr(Imm32(callFrameSize * sizeof(void*)), stackPointerRegister); |
| } |
| void removeCallFrame() |
| { |
| unsigned callFrameSize = m_pattern.m_body->m_callFrameSize; |
| if (callFrameSize) |
| addPtr(Imm32(callFrameSize * sizeof(void*)), stackPointerRegister); |
| } |
| |
| // Used to record subpatters, should only be called if compileMode is IncludeSubpatterns. |
| void setSubpatternStart(RegisterID reg, unsigned subpattern) |
| { |
| ASSERT(subpattern); |
| // FIXME: should be able to ASSERT(compileMode == IncludeSubpatterns), but then this function is conditionally NORETURN. :-( |
| store32(reg, Address(output, (subpattern << 1) * sizeof(int))); |
| } |
| void setSubpatternEnd(RegisterID reg, unsigned subpattern) |
| { |
| ASSERT(subpattern); |
| // FIXME: should be able to ASSERT(compileMode == IncludeSubpatterns), but then this function is conditionally NORETURN. :-( |
| store32(reg, Address(output, ((subpattern << 1) + 1) * sizeof(int))); |
| } |
| void clearSubpatternStart(unsigned subpattern) |
| { |
| ASSERT(subpattern); |
| // FIXME: should be able to ASSERT(compileMode == IncludeSubpatterns), but then this function is conditionally NORETURN. :-( |
| store32(TrustedImm32(-1), Address(output, (subpattern << 1) * sizeof(int))); |
| } |
| |
| // We use one of three different strategies to track the start of the current match, |
| // while matching. |
| // 1) If the pattern has a fixed size, do nothing! - we calculate the value lazily |
| // at the end of matching. This is irrespective of compileMode, and in this case |
| // these methods should never be called. |
| // 2) If we're compiling IncludeSubpatterns, 'output' contains a pointer to an output |
| // vector, store the match start in the output vector. |
| // 3) If we're compiling MatchOnly, 'output' is unused, store the match start directly |
| // in this register. |
| void setMatchStart(RegisterID reg) |
| { |
| ASSERT(!m_pattern.m_body->m_hasFixedSize); |
| if (compileMode == IncludeSubpatterns) |
| store32(reg, output); |
| else |
| move(reg, output); |
| } |
| void getMatchStart(RegisterID reg) |
| { |
| ASSERT(!m_pattern.m_body->m_hasFixedSize); |
| if (compileMode == IncludeSubpatterns) |
| load32(output, reg); |
| else |
| move(output, reg); |
| } |
| |
| enum YarrOpCode { |
| // These nodes wrap body alternatives - those in the main disjunction, |
| // rather than subpatterns or assertions. These are chained together in |
| // a doubly linked list, with a 'begin' node for the first alternative, |
| // a 'next' node for each subsequent alternative, and an 'end' node at |
| // the end. In the case of repeating alternatives, the 'end' node also |
| // has a reference back to 'begin'. |
| OpBodyAlternativeBegin, |
| OpBodyAlternativeNext, |
| OpBodyAlternativeEnd, |
| // Similar to the body alternatives, but used for subpatterns with two |
| // or more alternatives. |
| OpNestedAlternativeBegin, |
| OpNestedAlternativeNext, |
| OpNestedAlternativeEnd, |
| // Used for alternatives in subpatterns where there is only a single |
| // alternative (backtrackingis easier in these cases), or for alternatives |
| // which never need to be backtracked (those in parenthetical assertions, |
| // terminal subpatterns). |
| OpSimpleNestedAlternativeBegin, |
| OpSimpleNestedAlternativeNext, |
| OpSimpleNestedAlternativeEnd, |
| // Used to wrap 'Once' subpattern matches (quantityCount == 1). |
| OpParenthesesSubpatternOnceBegin, |
| OpParenthesesSubpatternOnceEnd, |
| // Used to wrap 'Terminal' subpattern matches (at the end of the regexp). |
| OpParenthesesSubpatternTerminalBegin, |
| OpParenthesesSubpatternTerminalEnd, |
| // Used to wrap parenthetical assertions. |
| OpParentheticalAssertionBegin, |
| OpParentheticalAssertionEnd, |
| // Wraps all simple terms (pattern characters, character classes). |
| OpTerm, |
| // Where an expression contains only 'once through' body alternatives |
| // and no repeating ones, this op is used to return match failure. |
| OpMatchFailed |
| }; |
| |
| // This structure is used to hold the compiled opcode information, |
| // including reference back to the original PatternTerm/PatternAlternatives, |
| // and JIT compilation data structures. |
| struct YarrOp { |
| explicit YarrOp(PatternTerm* term) |
| : m_op(OpTerm) |
| , m_term(term) |
| , m_isDeadCode(false) |
| { |
| } |
| |
| explicit YarrOp(YarrOpCode op) |
| : m_op(op) |
| , m_isDeadCode(false) |
| { |
| } |
| |
| // The operation, as a YarrOpCode, and also a reference to the PatternTerm. |
| YarrOpCode m_op; |
| PatternTerm* m_term; |
| |
| // For alternatives, this holds the PatternAlternative and doubly linked |
| // references to this alternative's siblings. In the case of the |
| // OpBodyAlternativeEnd node at the end of a section of repeating nodes, |
| // m_nextOp will reference the OpBodyAlternativeBegin node of the first |
| // repeating alternative. |
| PatternAlternative* m_alternative; |
| size_t m_previousOp; |
| size_t m_nextOp; |
| |
| // Used to record a set of Jumps out of the generated code, typically |
| // used for jumps out to backtracking code, and a single reentry back |
| // into the code for a node (likely where a backtrack will trigger |
| // rematching). |
| Label m_reentry; |
| JumpList m_jumps; |
| |
| // Used for backtracking when the prior alternative did not consume any |
| // characters but matched. |
| Jump m_zeroLengthMatch; |
| |
| // This flag is used to null out the second pattern character, when |
| // two are fused to match a pair together. |
| bool m_isDeadCode; |
| |
| // Currently used in the case of some of the more complex management of |
| // 'm_checked', to cache the offset used in this alternative, to avoid |
| // recalculating it. |
| int m_checkAdjust; |
| |
| // Used by OpNestedAlternativeNext/End to hold the pointer to the |
| // value that will be pushed into the pattern's frame to return to, |
| // upon backtracking back into the disjunction. |
| DataLabelPtr m_returnAddress; |
| }; |
| |
| // BacktrackingState |
| // This class encapsulates information about the state of code generation |
| // whilst generating the code for backtracking, when a term fails to match. |
| // Upon entry to code generation of the backtracking code for a given node, |
| // the Backtracking state will hold references to all control flow sources |
| // that are outputs in need of further backtracking from the prior node |
| // generated (which is the subsequent operation in the regular expression, |
| // and in the m_ops Vector, since we generated backtracking backwards). |
| // These references to control flow take the form of: |
| // - A jump list of jumps, to be linked to code that will backtrack them |
| // further. |
| // - A set of DataLabelPtr values, to be populated with values to be |
| // treated effectively as return addresses backtracking into complex |
| // subpatterns. |
| // - A flag indicating that the current sequence of generated code up to |
| // this point requires backtracking. |
| class BacktrackingState { |
| public: |
| BacktrackingState() |
| : m_pendingFallthrough(false) |
| { |
| } |
| |
| // Add a jump or jumps, a return address, or set the flag indicating |
| // that the current 'fallthrough' control flow requires backtracking. |
| void append(const Jump& jump) |
| { |
| m_laterFailures.append(jump); |
| } |
| void append(JumpList& jumpList) |
| { |
| m_laterFailures.append(jumpList); |
| } |
| void append(const DataLabelPtr& returnAddress) |
| { |
| m_pendingReturns.append(returnAddress); |
| } |
| void fallthrough() |
| { |
| ASSERT(!m_pendingFallthrough); |
| m_pendingFallthrough = true; |
| } |
| |
| // These methods clear the backtracking state, either linking to the |
| // current location, a provided label, or copying the backtracking out |
| // to a JumpList. All actions may require code generation to take place, |
| // and as such are passed a pointer to the assembler. |
| void link(MacroAssembler* assembler) |
| { |
| if (m_pendingReturns.size()) { |
| Label here(assembler); |
| for (unsigned i = 0; i < m_pendingReturns.size(); ++i) |
| m_backtrackRecords.append(ReturnAddressRecord(m_pendingReturns[i], here)); |
| m_pendingReturns.clear(); |
| } |
| m_laterFailures.link(assembler); |
| m_laterFailures.clear(); |
| m_pendingFallthrough = false; |
| } |
| void linkTo(Label label, MacroAssembler* assembler) |
| { |
| if (m_pendingReturns.size()) { |
| for (unsigned i = 0; i < m_pendingReturns.size(); ++i) |
| m_backtrackRecords.append(ReturnAddressRecord(m_pendingReturns[i], label)); |
| m_pendingReturns.clear(); |
| } |
| if (m_pendingFallthrough) |
| assembler->jump(label); |
| m_laterFailures.linkTo(label, assembler); |
| m_laterFailures.clear(); |
| m_pendingFallthrough = false; |
| } |
| void takeBacktracksToJumpList(JumpList& jumpList, MacroAssembler* assembler) |
| { |
| if (m_pendingReturns.size()) { |
| Label here(assembler); |
| for (unsigned i = 0; i < m_pendingReturns.size(); ++i) |
| m_backtrackRecords.append(ReturnAddressRecord(m_pendingReturns[i], here)); |
| m_pendingReturns.clear(); |
| m_pendingFallthrough = true; |
| } |
| if (m_pendingFallthrough) |
| jumpList.append(assembler->jump()); |
| jumpList.append(m_laterFailures); |
| m_laterFailures.clear(); |
| m_pendingFallthrough = false; |
| } |
| |
| bool isEmpty() |
| { |
| return m_laterFailures.empty() && m_pendingReturns.isEmpty() && !m_pendingFallthrough; |
| } |
| |
| // Called at the end of code generation to link all return addresses. |
| void linkDataLabels(LinkBuffer& linkBuffer) |
| { |
| ASSERT(isEmpty()); |
| for (unsigned i = 0; i < m_backtrackRecords.size(); ++i) |
| linkBuffer.patch(m_backtrackRecords[i].m_dataLabel, linkBuffer.locationOf(m_backtrackRecords[i].m_backtrackLocation)); |
| } |
| |
| private: |
| struct ReturnAddressRecord { |
| ReturnAddressRecord(DataLabelPtr dataLabel, Label backtrackLocation) |
| : m_dataLabel(dataLabel) |
| , m_backtrackLocation(backtrackLocation) |
| { |
| } |
| |
| DataLabelPtr m_dataLabel; |
| Label m_backtrackLocation; |
| }; |
| |
| JumpList m_laterFailures; |
| bool m_pendingFallthrough; |
| Vector<DataLabelPtr, 4> m_pendingReturns; |
| Vector<ReturnAddressRecord, 4> m_backtrackRecords; |
| }; |
| |
| // Generation methods: |
| // =================== |
| |
| // This method provides a default implementation of backtracking common |
| // to many terms; terms commonly jump out of the forwards matching path |
| // on any failed conditions, and add these jumps to the m_jumps list. If |
| // no special handling is required we can often just backtrack to m_jumps. |
| void backtrackTermDefault(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| m_backtrackingState.append(op.m_jumps); |
| } |
| |
| void generateAssertionBOL(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| |
| if (m_pattern.m_multiline) { |
| const RegisterID character = regT0; |
| |
| JumpList matchDest; |
| if (!term->inputPosition) |
| matchDest.append(branch32(Equal, index, Imm32(m_checked))); |
| |
| readCharacter((term->inputPosition - m_checked) - 1, character); |
| matchCharacterClass(character, matchDest, m_pattern.newlineCharacterClass()); |
| op.m_jumps.append(jump()); |
| |
| matchDest.link(this); |
| } else { |
| // Erk, really should poison out these alternatives early. :-/ |
| if (term->inputPosition) |
| op.m_jumps.append(jump()); |
| else |
| op.m_jumps.append(branch32(NotEqual, index, Imm32(m_checked))); |
| } |
| } |
| void backtrackAssertionBOL(size_t opIndex) |
| { |
| backtrackTermDefault(opIndex); |
| } |
| |
| void generateAssertionEOL(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| |
| if (m_pattern.m_multiline) { |
| const RegisterID character = regT0; |
| |
| JumpList matchDest; |
| if (term->inputPosition == m_checked) |
| matchDest.append(atEndOfInput()); |
| |
| readCharacter(term->inputPosition - m_checked, character); |
| matchCharacterClass(character, matchDest, m_pattern.newlineCharacterClass()); |
| op.m_jumps.append(jump()); |
| |
| matchDest.link(this); |
| } else { |
| if (term->inputPosition == m_checked) |
| op.m_jumps.append(notAtEndOfInput()); |
| // Erk, really should poison out these alternatives early. :-/ |
| else |
| op.m_jumps.append(jump()); |
| } |
| } |
| void backtrackAssertionEOL(size_t opIndex) |
| { |
| backtrackTermDefault(opIndex); |
| } |
| |
| // Also falls though on nextIsNotWordChar. |
| void matchAssertionWordchar(size_t opIndex, JumpList& nextIsWordChar, JumpList& nextIsNotWordChar) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| |
| const RegisterID character = regT0; |
| |
| if (term->inputPosition == m_checked) |
| nextIsNotWordChar.append(atEndOfInput()); |
| |
| readCharacter((term->inputPosition - m_checked), character); |
| matchCharacterClass(character, nextIsWordChar, m_pattern.wordcharCharacterClass()); |
| } |
| |
| void generateAssertionWordBoundary(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| |
| const RegisterID character = regT0; |
| |
| Jump atBegin; |
| JumpList matchDest; |
| if (!term->inputPosition) |
| atBegin = branch32(Equal, index, Imm32(m_checked)); |
| readCharacter((term->inputPosition - m_checked) - 1, character); |
| matchCharacterClass(character, matchDest, m_pattern.wordcharCharacterClass()); |
| if (!term->inputPosition) |
| atBegin.link(this); |
| |
| // We fall through to here if the last character was not a wordchar. |
| JumpList nonWordCharThenWordChar; |
| JumpList nonWordCharThenNonWordChar; |
| if (term->invert()) { |
| matchAssertionWordchar(opIndex, nonWordCharThenNonWordChar, nonWordCharThenWordChar); |
| nonWordCharThenWordChar.append(jump()); |
| } else { |
| matchAssertionWordchar(opIndex, nonWordCharThenWordChar, nonWordCharThenNonWordChar); |
| nonWordCharThenNonWordChar.append(jump()); |
| } |
| op.m_jumps.append(nonWordCharThenNonWordChar); |
| |
| // We jump here if the last character was a wordchar. |
| matchDest.link(this); |
| JumpList wordCharThenWordChar; |
| JumpList wordCharThenNonWordChar; |
| if (term->invert()) { |
| matchAssertionWordchar(opIndex, wordCharThenNonWordChar, wordCharThenWordChar); |
| wordCharThenWordChar.append(jump()); |
| } else { |
| matchAssertionWordchar(opIndex, wordCharThenWordChar, wordCharThenNonWordChar); |
| // This can fall-though! |
| } |
| |
| op.m_jumps.append(wordCharThenWordChar); |
| |
| nonWordCharThenWordChar.link(this); |
| wordCharThenNonWordChar.link(this); |
| } |
| void backtrackAssertionWordBoundary(size_t opIndex) |
| { |
| backtrackTermDefault(opIndex); |
| } |
| |
| void generatePatternCharacterOnce(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| |
| if (op.m_isDeadCode) |
| return; |
| |
| // m_ops always ends with a OpBodyAlternativeEnd or OpMatchFailed |
| // node, so there must always be at least one more node. |
| ASSERT(opIndex + 1 < m_ops.size()); |
| YarrOp* nextOp = &m_ops[opIndex + 1]; |
| |
| PatternTerm* term = op.m_term; |
| UChar ch = term->patternCharacter; |
| |
| if ((ch > 0xff) && (m_charSize == Char8)) { |
| // Have a 16 bit pattern character and an 8 bit string - short circuit |
| op.m_jumps.append(jump()); |
| return; |
| } |
| |
| const RegisterID character = regT0; |
| int maxCharactersAtOnce = m_charSize == Char8 ? 4 : 2; |
| unsigned ignoreCaseMask = 0; |
| int allCharacters = ch; |
| int numberCharacters; |
| int startTermPosition = term->inputPosition; |
| |
| // For case-insesitive compares, non-ascii characters that have different |
| // upper & lower case representations are converted to a character class. |
| ASSERT(!m_pattern.m_ignoreCase || isASCIIAlpha(ch) || isCanonicallyUnique(ch)); |
| |
| if (m_pattern.m_ignoreCase && isASCIIAlpha(ch)) |
| ignoreCaseMask |= 32; |
| |
| for (numberCharacters = 1; numberCharacters < maxCharactersAtOnce && nextOp->m_op == OpTerm; ++numberCharacters, nextOp = &m_ops[opIndex + numberCharacters]) { |
| PatternTerm* nextTerm = nextOp->m_term; |
| |
| if (nextTerm->type != PatternTerm::TypePatternCharacter |
| || nextTerm->quantityType != QuantifierFixedCount |
| || nextTerm->quantityCount != 1 |
| || nextTerm->inputPosition != (startTermPosition + numberCharacters)) |
| break; |
| |
| nextOp->m_isDeadCode = true; |
| |
| int shiftAmount = (m_charSize == Char8 ? 8 : 16) * numberCharacters; |
| |
| UChar currentCharacter = nextTerm->patternCharacter; |
| |
| if ((currentCharacter > 0xff) && (m_charSize == Char8)) { |
| // Have a 16 bit pattern character and an 8 bit string - short circuit |
| op.m_jumps.append(jump()); |
| return; |
| } |
| |
| // For case-insesitive compares, non-ascii characters that have different |
| // upper & lower case representations are converted to a character class. |
| ASSERT(!m_pattern.m_ignoreCase || isASCIIAlpha(currentCharacter) || isCanonicallyUnique(currentCharacter)); |
| |
| allCharacters |= (currentCharacter << shiftAmount); |
| |
| if ((m_pattern.m_ignoreCase) && (isASCIIAlpha(currentCharacter))) |
| ignoreCaseMask |= 32 << shiftAmount; |
| } |
| |
| if (m_charSize == Char8) { |
| switch (numberCharacters) { |
| case 1: |
| op.m_jumps.append(jumpIfCharNotEquals(ch, startTermPosition - m_checked, character)); |
| return; |
| case 2: { |
| BaseIndex address(input, index, TimesOne, (startTermPosition - m_checked) * sizeof(LChar)); |
| load16Unaligned(address, character); |
| break; |
| } |
| case 3: { |
| BaseIndex highAddress(input, index, TimesOne, (startTermPosition - m_checked) * sizeof(LChar)); |
| load16Unaligned(highAddress, character); |
| if (ignoreCaseMask) |
| or32(Imm32(ignoreCaseMask), character); |
| op.m_jumps.append(branch32(NotEqual, character, Imm32((allCharacters & 0xffff) | ignoreCaseMask))); |
| op.m_jumps.append(jumpIfCharNotEquals(allCharacters >> 16, startTermPosition + 2 - m_checked, character)); |
| return; |
| } |
| case 4: { |
| BaseIndex address(input, index, TimesOne, (startTermPosition - m_checked) * sizeof(LChar)); |
| load32WithUnalignedHalfWords(address, character); |
| break; |
| } |
| } |
| } else { |
| switch (numberCharacters) { |
| case 1: |
| op.m_jumps.append(jumpIfCharNotEquals(ch, term->inputPosition - m_checked, character)); |
| return; |
| case 2: |
| BaseIndex address(input, index, TimesTwo, (term->inputPosition - m_checked) * sizeof(UChar)); |
| load32WithUnalignedHalfWords(address, character); |
| break; |
| } |
| } |
| |
| if (ignoreCaseMask) |
| or32(Imm32(ignoreCaseMask), character); |
| op.m_jumps.append(branch32(NotEqual, character, Imm32(allCharacters | ignoreCaseMask))); |
| return; |
| } |
| void backtrackPatternCharacterOnce(size_t opIndex) |
| { |
| backtrackTermDefault(opIndex); |
| } |
| |
| void generatePatternCharacterFixed(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| UChar ch = term->patternCharacter; |
| |
| const RegisterID character = regT0; |
| const RegisterID countRegister = regT1; |
| |
| move(index, countRegister); |
| sub32(Imm32(term->quantityCount.unsafeGet()), countRegister); |
| |
| Label loop(this); |
| Checked<int, RecordOverflow> checkedOffset(term->inputPosition - m_checked + Checked<int64_t>(term->quantityCount)); |
| if (!checkedOffset.hasOverflowed()) { |
| checkedOffset *= static_cast<int>(m_charSize == Char8 ? sizeof(char) : sizeof(UChar)); |
| } |
| if (checkedOffset.hasOverflowed()) { |
| // There has been an integer overflow, so bail out and fall back to |
| // the interpreter. |
| m_shouldFallBack = true; |
| return; |
| } |
| BaseIndex address(input, countRegister, m_charScale, checkedOffset.unsafeGet()); |
| |
| if (m_charSize == Char8) |
| load8(address, character); |
| else |
| load16(address, character); |
| |
| // For case-insesitive compares, non-ascii characters that have different |
| // upper & lower case representations are converted to a character class. |
| ASSERT(!m_pattern.m_ignoreCase || isASCIIAlpha(ch) || isCanonicallyUnique(ch)); |
| if (m_pattern.m_ignoreCase && isASCIIAlpha(ch)) { |
| or32(TrustedImm32(0x20), character); |
| ch |= 0x20; |
| } |
| |
| op.m_jumps.append(branch32(NotEqual, character, Imm32(ch))); |
| add32(TrustedImm32(1), countRegister); |
| branch32(NotEqual, countRegister, index).linkTo(loop, this); |
| } |
| void backtrackPatternCharacterFixed(size_t opIndex) |
| { |
| backtrackTermDefault(opIndex); |
| } |
| |
| void generatePatternCharacterGreedy(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| UChar ch = term->patternCharacter; |
| |
| const RegisterID character = regT0; |
| const RegisterID countRegister = regT1; |
| |
| move(TrustedImm32(0), countRegister); |
| |
| // Unless have a 16 bit pattern character and an 8 bit string - short circuit |
| if (!((ch > 0xff) && (m_charSize == Char8))) { |
| JumpList failures; |
| Label loop(this); |
| failures.append(atEndOfInput()); |
| failures.append(jumpIfCharNotEquals(ch, term->inputPosition - m_checked, character)); |
| |
| add32(TrustedImm32(1), countRegister); |
| add32(TrustedImm32(1), index); |
| if (term->quantityCount == quantifyInfinite) |
| jump(loop); |
| else |
| branch32(NotEqual, countRegister, Imm32(term->quantityCount.unsafeGet())).linkTo(loop, this); |
| |
| failures.link(this); |
| } |
| op.m_reentry = label(); |
| |
| storeToFrame(countRegister, term->frameLocation); |
| } |
| void backtrackPatternCharacterGreedy(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| |
| const RegisterID countRegister = regT1; |
| |
| m_backtrackingState.link(this); |
| |
| loadFromFrame(term->frameLocation, countRegister); |
| m_backtrackingState.append(branchTest32(Zero, countRegister)); |
| sub32(TrustedImm32(1), countRegister); |
| sub32(TrustedImm32(1), index); |
| jump(op.m_reentry); |
| } |
| |
| void generatePatternCharacterNonGreedy(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| |
| const RegisterID countRegister = regT1; |
| |
| move(TrustedImm32(0), countRegister); |
| op.m_reentry = label(); |
| storeToFrame(countRegister, term->frameLocation); |
| } |
| void backtrackPatternCharacterNonGreedy(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| UChar ch = term->patternCharacter; |
| |
| const RegisterID character = regT0; |
| const RegisterID countRegister = regT1; |
| |
| m_backtrackingState.link(this); |
| |
| loadFromFrame(term->frameLocation, countRegister); |
| |
| // Unless have a 16 bit pattern character and an 8 bit string - short circuit |
| if (!((ch > 0xff) && (m_charSize == Char8))) { |
| JumpList nonGreedyFailures; |
| nonGreedyFailures.append(atEndOfInput()); |
| if (term->quantityCount != quantifyInfinite) |
| nonGreedyFailures.append(branch32(Equal, countRegister, Imm32(term->quantityCount.unsafeGet()))); |
| nonGreedyFailures.append(jumpIfCharNotEquals(ch, term->inputPosition - m_checked, character)); |
| |
| add32(TrustedImm32(1), countRegister); |
| add32(TrustedImm32(1), index); |
| |
| jump(op.m_reentry); |
| nonGreedyFailures.link(this); |
| } |
| |
| sub32(countRegister, index); |
| m_backtrackingState.fallthrough(); |
| } |
| |
| void generateCharacterClassOnce(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| |
| const RegisterID character = regT0; |
| |
| JumpList matchDest; |
| readCharacter(term->inputPosition - m_checked, character); |
| matchCharacterClass(character, matchDest, term->characterClass); |
| |
| if (term->invert()) |
| op.m_jumps.append(matchDest); |
| else { |
| op.m_jumps.append(jump()); |
| matchDest.link(this); |
| } |
| } |
| void backtrackCharacterClassOnce(size_t opIndex) |
| { |
| backtrackTermDefault(opIndex); |
| } |
| |
| void generateCharacterClassFixed(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| |
| const RegisterID character = regT0; |
| const RegisterID countRegister = regT1; |
| |
| move(index, countRegister); |
| sub32(Imm32(term->quantityCount.unsafeGet()), countRegister); |
| |
| Label loop(this); |
| JumpList matchDest; |
| Checked<int, RecordOverflow> checkedOffset(term->inputPosition - m_checked + Checked<int64_t>(term->quantityCount)); |
| if (!checkedOffset.hasOverflowed()) { |
| checkedOffset *= static_cast<int>(m_charSize == Char8 ? sizeof(char) : sizeof(UChar)); |
| } |
| if (checkedOffset.hasOverflowed()) { |
| // If there has been integer overflow, fall back to the interpreter. |
| m_shouldFallBack = true; |
| return; |
| } |
| if (m_charSize == Char8) |
| load8(BaseIndex(input, countRegister, TimesOne, checkedOffset.unsafeGet()), character); |
| else |
| load16(BaseIndex(input, countRegister, TimesTwo, checkedOffset.unsafeGet()), character); |
| matchCharacterClass(character, matchDest, term->characterClass); |
| |
| if (term->invert()) |
| op.m_jumps.append(matchDest); |
| else { |
| op.m_jumps.append(jump()); |
| matchDest.link(this); |
| } |
| |
| add32(TrustedImm32(1), countRegister); |
| branch32(NotEqual, countRegister, index).linkTo(loop, this); |
| } |
| void backtrackCharacterClassFixed(size_t opIndex) |
| { |
| backtrackTermDefault(opIndex); |
| } |
| |
| void generateCharacterClassGreedy(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| |
| const RegisterID character = regT0; |
| const RegisterID countRegister = regT1; |
| |
| move(TrustedImm32(0), countRegister); |
| |
| JumpList failures; |
| Label loop(this); |
| failures.append(atEndOfInput()); |
| |
| if (term->invert()) { |
| readCharacter(term->inputPosition - m_checked, character); |
| matchCharacterClass(character, failures, term->characterClass); |
| } else { |
| JumpList matchDest; |
| readCharacter(term->inputPosition - m_checked, character); |
| matchCharacterClass(character, matchDest, term->characterClass); |
| failures.append(jump()); |
| matchDest.link(this); |
| } |
| |
| add32(TrustedImm32(1), countRegister); |
| add32(TrustedImm32(1), index); |
| if (term->quantityCount != quantifyInfinite) { |
| branch32(NotEqual, countRegister, Imm32(term->quantityCount.unsafeGet())).linkTo(loop, this); |
| failures.append(jump()); |
| } else |
| jump(loop); |
| |
| failures.link(this); |
| op.m_reentry = label(); |
| |
| storeToFrame(countRegister, term->frameLocation); |
| } |
| void backtrackCharacterClassGreedy(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| |
| const RegisterID countRegister = regT1; |
| |
| m_backtrackingState.link(this); |
| |
| loadFromFrame(term->frameLocation, countRegister); |
| m_backtrackingState.append(branchTest32(Zero, countRegister)); |
| sub32(TrustedImm32(1), countRegister); |
| sub32(TrustedImm32(1), index); |
| jump(op.m_reentry); |
| } |
| |
| void generateCharacterClassNonGreedy(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| |
| const RegisterID countRegister = regT1; |
| |
| move(TrustedImm32(0), countRegister); |
| op.m_reentry = label(); |
| storeToFrame(countRegister, term->frameLocation); |
| } |
| void backtrackCharacterClassNonGreedy(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| |
| const RegisterID character = regT0; |
| const RegisterID countRegister = regT1; |
| |
| JumpList nonGreedyFailures; |
| |
| m_backtrackingState.link(this); |
| |
| loadFromFrame(term->frameLocation, countRegister); |
| |
| nonGreedyFailures.append(atEndOfInput()); |
| nonGreedyFailures.append(branch32(Equal, countRegister, Imm32(term->quantityCount.unsafeGet()))); |
| |
| JumpList matchDest; |
| readCharacter(term->inputPosition - m_checked, character); |
| matchCharacterClass(character, matchDest, term->characterClass); |
| |
| if (term->invert()) |
| nonGreedyFailures.append(matchDest); |
| else { |
| nonGreedyFailures.append(jump()); |
| matchDest.link(this); |
| } |
| |
| add32(TrustedImm32(1), countRegister); |
| add32(TrustedImm32(1), index); |
| |
| jump(op.m_reentry); |
| |
| nonGreedyFailures.link(this); |
| sub32(countRegister, index); |
| m_backtrackingState.fallthrough(); |
| } |
| |
| void generateDotStarEnclosure(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| |
| const RegisterID character = regT0; |
| const RegisterID matchPos = regT1; |
| |
| JumpList foundBeginningNewLine; |
| JumpList saveStartIndex; |
| JumpList foundEndingNewLine; |
| |
| ASSERT(!m_pattern.m_body->m_hasFixedSize); |
| getMatchStart(matchPos); |
| |
| saveStartIndex.append(branchTest32(Zero, matchPos)); |
| Label findBOLLoop(this); |
| sub32(TrustedImm32(1), matchPos); |
| if (m_charSize == Char8) |
| load8(BaseIndex(input, matchPos, TimesOne, 0), character); |
| else |
| load16(BaseIndex(input, matchPos, TimesTwo, 0), character); |
| matchCharacterClass(character, foundBeginningNewLine, m_pattern.newlineCharacterClass()); |
| branchTest32(NonZero, matchPos).linkTo(findBOLLoop, this); |
| saveStartIndex.append(jump()); |
| |
| foundBeginningNewLine.link(this); |
| add32(TrustedImm32(1), matchPos); // Advance past newline |
| saveStartIndex.link(this); |
| |
| if (!m_pattern.m_multiline && term->anchors.bolAnchor) |
| op.m_jumps.append(branchTest32(NonZero, matchPos)); |
| |
| ASSERT(!m_pattern.m_body->m_hasFixedSize); |
| setMatchStart(matchPos); |
| |
| move(index, matchPos); |
| |
| Label findEOLLoop(this); |
| foundEndingNewLine.append(branch32(Equal, matchPos, length)); |
| if (m_charSize == Char8) |
| load8(BaseIndex(input, matchPos, TimesOne, 0), character); |
| else |
| load16(BaseIndex(input, matchPos, TimesTwo, 0), character); |
| matchCharacterClass(character, foundEndingNewLine, m_pattern.newlineCharacterClass()); |
| add32(TrustedImm32(1), matchPos); |
| jump(findEOLLoop); |
| |
| foundEndingNewLine.link(this); |
| |
| if (!m_pattern.m_multiline && term->anchors.eolAnchor) |
| op.m_jumps.append(branch32(NotEqual, matchPos, length)); |
| |
| move(matchPos, index); |
| } |
| |
| void backtrackDotStarEnclosure(size_t opIndex) |
| { |
| backtrackTermDefault(opIndex); |
| } |
| |
| // Code generation/backtracking for simple terms |
| // (pattern characters, character classes, and assertions). |
| // These methods farm out work to the set of functions above. |
| void generateTerm(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| |
| switch (term->type) { |
| case PatternTerm::TypePatternCharacter: |
| switch (term->quantityType) { |
| case QuantifierFixedCount: |
| if (term->quantityCount == 1) |
| generatePatternCharacterOnce(opIndex); |
| else |
| generatePatternCharacterFixed(opIndex); |
| break; |
| case QuantifierGreedy: |
| generatePatternCharacterGreedy(opIndex); |
| break; |
| case QuantifierNonGreedy: |
| generatePatternCharacterNonGreedy(opIndex); |
| break; |
| } |
| break; |
| |
| case PatternTerm::TypeCharacterClass: |
| switch (term->quantityType) { |
| case QuantifierFixedCount: |
| if (term->quantityCount == 1) |
| generateCharacterClassOnce(opIndex); |
| else |
| generateCharacterClassFixed(opIndex); |
| break; |
| case QuantifierGreedy: |
| generateCharacterClassGreedy(opIndex); |
| break; |
| case QuantifierNonGreedy: |
| generateCharacterClassNonGreedy(opIndex); |
| break; |
| } |
| break; |
| |
| case PatternTerm::TypeAssertionBOL: |
| generateAssertionBOL(opIndex); |
| break; |
| |
| case PatternTerm::TypeAssertionEOL: |
| generateAssertionEOL(opIndex); |
| break; |
| |
| case PatternTerm::TypeAssertionWordBoundary: |
| generateAssertionWordBoundary(opIndex); |
| break; |
| |
| case PatternTerm::TypeForwardReference: |
| break; |
| |
| case PatternTerm::TypeParenthesesSubpattern: |
| case PatternTerm::TypeParentheticalAssertion: |
| ASSERT_NOT_REACHED(); |
| case PatternTerm::TypeBackReference: |
| m_shouldFallBack = true; |
| break; |
| case PatternTerm::TypeDotStarEnclosure: |
| generateDotStarEnclosure(opIndex); |
| break; |
| } |
| } |
| void backtrackTerm(size_t opIndex) |
| { |
| YarrOp& op = m_ops[opIndex]; |
| PatternTerm* term = op.m_term; |
| |
| switch (term->type) { |
| case PatternTerm::TypePatternCharacter: |
| switch (term->quantityType) { |
| case QuantifierFixedCount: |
| if (term->quantityCount == 1) |
| backtrackPatternCharacterOnce(opIndex); |
| else |
| backtrackPatternCharacterFixed(opIndex); |
| break; |
| case QuantifierGreedy: |
| backtrackPatternCharacterGreedy(opIndex); |
| break; |
| case QuantifierNonGreedy: |
| backtrackPatternCharacterNonGreedy(opIndex); |
| break; |
| } |
| break; |
| |
| case PatternTerm::TypeCharacterClass: |
| switch (term->quantityType) { |
| case QuantifierFixedCount: |
| if (term->quantityCount == 1) |
| backtrackCharacterClassOnce(opIndex); |
| else |
| backtrackCharacterClassFixed(opIndex); |
| break; |
| case QuantifierGreedy: |
| backtrackCharacterClassGreedy(opIndex); |
| break; |
| case QuantifierNonGreedy: |
| backtrackCharacterClassNonGreedy(opIndex); |
| break; |
| } |
| break; |
| |
| case PatternTerm::TypeAssertionBOL: |
| backtrackAssertionBOL(opIndex); |
| break; |
| |
| case PatternTerm::TypeAssertionEOL: |
| backtrackAssertionEOL(opIndex); |
| break; |
| |
| case PatternTerm::TypeAssertionWordBoundary: |
| backtrackAssertionWordBoundary(opIndex); |
| break; |
| |
| case PatternTerm::TypeForwardReference: |
| break; |
| |
| case PatternTerm::TypeParenthesesSubpattern: |
| case PatternTerm::TypeParentheticalAssertion: |
| ASSERT_NOT_REACHED(); |
| |
| case PatternTerm::TypeDotStarEnclosure: |
| backtrackDotStarEnclosure(opIndex); |
| break; |
| |
| case PatternTerm::TypeBackReference: |
| m_shouldFallBack = true; |
| break; |
| } |
| } |
| |
| void generate() |
| { |
| // Forwards generate the matching code. |
| ASSERT(m_ops.size()); |
| size_t opIndex = 0; |
| |
| do { |
| YarrOp& op = m_ops[opIndex]; |
| switch (op.m_op) { |
| |
| case OpTerm: |
| generateTerm(opIndex); |
| break; |
| |
| // OpBodyAlternativeBegin/Next/End |
| // |
| // These nodes wrap the set of alternatives in the body of the regular expression. |
| // There may be either one or two chains of OpBodyAlternative nodes, one representing |
| // the 'once through' sequence of alternatives (if any exist), and one representing |
| // the repeating alternatives (again, if any exist). |
| // |
| // Upon normal entry to the Begin alternative, we will check that input is available. |
| // Reentry to the Begin alternative will take place after the check has taken place, |
| // and will assume that the input position has already been progressed as appropriate. |
| // |
| // Entry to subsequent Next/End alternatives occurs when the prior alternative has |
| // successfully completed a match - return a success state from JIT code. |
| // |
| // Next alternatives allow for reentry optimized to suit backtracking from its |
| // preceding alternative. It expects the input position to still be set to a position |
| // appropriate to its predecessor, and it will only perform an input check if the |
| // predecessor had a minimum size less than its own. |
| // |
| // In the case 'once through' expressions, the End node will also have a reentry |
| // point to jump to when the last alternative fails. Again, this expects the input |
| // position to still reflect that expected by the prior alternative. |
| case OpBodyAlternativeBegin: { |
| PatternAlternative* alternative = op.m_alternative; |
| |
| // Upon entry at the head of the set of alternatives, check if input is available |
| // to run the first alternative. (This progresses the input position). |
| op.m_jumps.append(jumpIfNoAvailableInput(alternative->m_minimumSize)); |
| // We will reenter after the check, and assume the input position to have been |
| // set as appropriate to this alternative. |
| op.m_reentry = label(); |
| |
| m_checked += alternative->m_minimumSize; |
| break; |
| } |
| case OpBodyAlternativeNext: |
| case OpBodyAlternativeEnd: { |
| PatternAlternative* priorAlternative = m_ops[op.m_previousOp].m_alternative; |
| PatternAlternative* alternative = op.m_alternative; |
| |
| // If we get here, the prior alternative matched - return success. |
| |
| // Adjust the stack pointer to remove the pattern's frame. |
| #if !WTF_CPU_SPARC |
| removeCallFrame(); |
| #endif |
| |
| // Load appropriate values into the return register and the first output |
| // slot, and return. In the case of pattern with a fixed size, we will |
| // not have yet set the value in the first |
| ASSERT(index != returnRegister); |
| if (m_pattern.m_body->m_hasFixedSize) { |
| move(index, returnRegister); |
| if (priorAlternative->m_minimumSize) |
| sub32(Imm32(priorAlternative->m_minimumSize), returnRegister); |
| if (compileMode == IncludeSubpatterns) |
| store32(returnRegister, output); |
| } else |
| getMatchStart(returnRegister); |
| if (compileMode == IncludeSubpatterns) |
| store32(index, Address(output, 4)); |
| #if WTF_CPU_X86_64 |
| // upper 32bit to 0 |
| move32(returnRegister, returnRegister); |
| lshiftPtr(Imm32(32), index); |
| orPtr(index, returnRegister); |
| #else |
| move(index, returnRegister2); |
| #endif |
| |
| generateReturn(); |
| |
| // This is the divide between the tail of the prior alternative, above, and |
| // the head of the subsequent alternative, below. |
| |
| if (op.m_op == OpBodyAlternativeNext) { |
| // This is the reentry point for the Next alternative. We expect any code |
| // that jumps here to do so with the input position matching that of the |
| // PRIOR alteranative, and we will only check input availability if we |
| // need to progress it forwards. |
| op.m_reentry = label(); |
| if (alternative->m_minimumSize > priorAlternative->m_minimumSize) { |
| add32(Imm32(alternative->m_minimumSize - priorAlternative->m_minimumSize), index); |
| op.m_jumps.append(jumpIfNoAvailableInput()); |
| } else if (priorAlternative->m_minimumSize > alternative->m_minimumSize) |
| sub32(Imm32(priorAlternative->m_minimumSize - alternative->m_minimumSize), index); |
| } else if (op.m_nextOp == notFound) { |
| // This is the reentry point for the End of 'once through' alternatives, |
| // jumped to when the last alternative fails to match. |
| op.m_reentry = label(); |
| sub32(Imm32(priorAlternative->m_minimumSize), index); |
| } |
| |
| if (op.m_op == OpBodyAlternativeNext) |
| m_checked += alternative->m_minimumSize; |
| m_checked -= priorAlternative->m_minimumSize; |
| break; |
| } |
| |
| // OpSimpleNestedAlternativeBegin/Next/End |
| // OpNestedAlternativeBegin/Next/End |
| // |
| // These nodes are used to handle sets of alternatives that are nested within |
| // subpatterns and parenthetical assertions. The 'simple' forms are used where |
| // we do not need to be able to backtrack back into any alternative other than |
| // the last, the normal forms allow backtracking into any alternative. |
| // |
| // Each Begin/Next node is responsible for planting an input check to ensure |
| // sufficient input is available on entry. Next nodes additionally need to |
| // jump to the end - Next nodes use the End node's m_jumps list to hold this |
| // set of jumps. |
| // |
| // In the non-simple forms, successful alternative matches must store a |
| // 'return address' using a DataLabelPtr, used to store the address to jump |
| // to when backtracking, to get to the code for the appropriate alternative. |
| case OpSimpleNestedAlternativeBegin: |
| case OpNestedAlternativeBegin: { |
| PatternTerm* term = op.m_term; |
| PatternAlternative* alternative = op.m_alternative; |
| PatternDisjunction* disjunction = term->parentheses.disjunction; |
| |
| // Calculate how much input we need to check for, and if non-zero check. |
| op.m_checkAdjust = alternative->m_minimumSize; |
| if ((term->quantityType == QuantifierFixedCount) && (term->type != PatternTerm::TypeParentheticalAssertion)) |
| op.m_checkAdjust -= disjunction->m_minimumSize; |
| if (op.m_checkAdjust) |
| op.m_jumps.append(jumpIfNoAvailableInput(op.m_checkAdjust)); |
| |
| m_checked += op.m_checkAdjust; |
| break; |
| } |
| case OpSimpleNestedAlternativeNext: |
| case OpNestedAlternativeNext: { |
| PatternTerm* term = op.m_term; |
| PatternAlternative* alternative = op.m_alternative; |
| PatternDisjunction* disjunction = term->parentheses.disjunction; |
| |
| // In the non-simple case, store a 'return address' so we can backtrack correctly. |
| if (op.m_op == OpNestedAlternativeNext) { |
| unsigned parenthesesFrameLocation = term->frameLocation; |
| unsigned alternativeFrameLocation = parenthesesFrameLocation; |
| if (term->quantityType != QuantifierFixedCount) |
| alternativeFrameLocation += YarrStackSpaceForBackTrackInfoParenthesesOnce; |
| op.m_returnAddress = storeToFrameWithPatch(alternativeFrameLocation); |
| } |
| |
| if (term->quantityType != QuantifierFixedCount && !m_ops[op.m_previousOp].m_alternative->m_minimumSize) { |
| // If the previous alternative matched without consuming characters then |
| // backtrack to try to match while consumming some input. |
| op.m_zeroLengthMatch = branch32(Equal, index, Address(stackPointerRegister, term->frameLocation * sizeof(void*))); |
| } |
| |
| // If we reach here then the last alternative has matched - jump to the |
| // End node, to skip over any further alternatives. |
| // |
| // FIXME: this is logically O(N^2) (though N can be expected to be very |
| // small). We could avoid this either by adding an extra jump to the JIT |
| // data structures, or by making backtracking code that jumps to Next |
| // alternatives are responsible for checking that input is available (if |
| // we didn't need to plant the input checks, then m_jumps would be free). |
| YarrOp* endOp = &m_ops[op.m_nextOp]; |
| while (endOp->m_nextOp != notFound) { |
| ASSERT(endOp->m_op == OpSimpleNestedAlternativeNext || endOp->m_op == OpNestedAlternativeNext); |
| endOp = &m_ops[endOp->m_nextOp]; |
| } |
| ASSERT(endOp->m_op == OpSimpleNestedAlternativeEnd || endOp->m_op == OpNestedAlternativeEnd); |
| endOp->m_jumps.append(jump()); |
| |
| // This is the entry point for the next alternative. |
| op.m_reentry = label(); |
| |
| // Calculate how much input we need to check for, and if non-zero check. |
| op.m_checkAdjust = alternative->m_minimumSize; |
| if ((term->quantityType == QuantifierFixedCount) && (term->type != PatternTerm::TypeParentheticalAssertion)) |
| op.m_checkAdjust -= disjunction->m_minimumSize; |
| if (op.m_checkAdjust) |
| op.m_jumps.append(jumpIfNoAvailableInput(op.m_checkAdjust)); |
| |
| YarrOp& lastOp = m_ops[op.m_previousOp]; |
| m_checked -= lastOp.m_checkAdjust; |
| m_checked += op.m_checkAdjust; |
| break; |
| } |
| case OpSimpleNestedAlternativeEnd: |
| case OpNestedAlternativeEnd: { |
| PatternTerm* term = op.m_term; |
| |
| // In the non-simple case, store a 'return address' so we can backtrack correctly. |
| if (op.m_op == OpNestedAlternativeEnd) { |
| unsigned parenthesesFrameLocation = term->frameLocation; |
| unsigned alternativeFrameLocation = parenthesesFrameLocation; |
| if (term->quantityType != QuantifierFixedCount) |
| alternativeFrameLocation += YarrStackSpaceForBackTrackInfoParenthesesOnce; |
| op.m_returnAddress = storeToFrameWithPatch(alternativeFrameLocation); |
| } |
| |
| if (term->quantityType != QuantifierFixedCount && !m_ops[op.m_previousOp].m_alternative->m_minimumSize) { |
| // If the previous alternative matched without consuming characters then |
| // backtrack to try to match while consumming some input. |
| op.m_zeroLengthMatch = branch32(Equal, index, Address(stackPointerRegister, term->frameLocation * sizeof(void*))); |
| } |
| |
| // If this set of alternatives contains more than one alternative, |
| // then the Next nodes will have planted jumps to the End, and added |
| // them to this node's m_jumps list. |
| op.m_jumps.link(this); |
| op.m_jumps.clear(); |
| |
| YarrOp& lastOp = m_ops[op.m_previousOp]; |
| m_checked -= lastOp.m_checkAdjust; |
| break; |
| } |
| |
| // OpParenthesesSubpatternOnceBegin/End |
| // |
| // These nodes support (optionally) capturing subpatterns, that have a |
| // quantity count of 1 (this covers fixed once, and ?/?? quantifiers). |
| case OpParenthesesSubpatternOnceBegin: { |
| PatternTerm* term = op.m_term; |
| unsigned parenthesesFrameLocation = term->frameLocation; |
| const RegisterID indexTemporary = regT0; |
| ASSERT(term->quantityCount == 1); |
| |
| // Upon entry to a Greedy quantified set of parenthese store the index. |
| // We'll use this for two purposes: |
| // - To indicate which iteration we are on of mathing the remainder of |
| // the expression after the parentheses - the first, including the |
| // match within the parentheses, or the second having skipped over them. |
| // - To check for empty matches, which must be rejected. |
| // |
| // At the head of a NonGreedy set of parentheses we'll immediately set the |
| // value on the stack to -1 (indicating a match skipping the subpattern), |
| // and plant a jump to the end. We'll also plant a label to backtrack to |
| // to reenter the subpattern later, with a store to set up index on the |
| // second iteration. |
| // |
| // FIXME: for capturing parens, could use the index in the capture array? |
| if (term->quantityType == QuantifierGreedy) |
| storeToFrame(index, parenthesesFrameLocation); |
| else if (term->quantityType == QuantifierNonGreedy) { |
| storeToFrame(TrustedImm32(-1), parenthesesFrameLocation); |
| op.m_jumps.append(jump()); |
| op.m_reentry = label(); |
| storeToFrame(index, parenthesesFrameLocation); |
| } |
| |
| // If the parenthese are capturing, store the starting index value to the |
| // captures array, offsetting as necessary. |
| // |
| // FIXME: could avoid offsetting this value in JIT code, apply |
| // offsets only afterwards, at the point the results array is |
| // being accessed. |
| if (term->capture() && compileMode == IncludeSubpatterns) { |
| int inputOffset = term->inputPosition - m_checked; |
| if (term->quantityType == QuantifierFixedCount) |
| inputOffset -= term->parentheses.disjunction->m_minimumSize; |
| if (inputOffset) { |
| move(index, indexTemporary); |
| add32(Imm32(inputOffset), indexTemporary); |
| setSubpatternStart(indexTemporary, term->parentheses.subpatternId); |
| } else |
| setSubpatternStart(index, term->parentheses.subpatternId); |
| } |
| break; |
| } |
| case OpParenthesesSubpatternOnceEnd: { |
| PatternTerm* term = op.m_term; |
| const RegisterID indexTemporary = regT0; |
| ASSERT(term->quantityCount == 1); |
| |
| #ifndef NDEBUG |
| // Runtime ASSERT to make sure that the nested alternative handled the |
| // "no input consumed" check. |
| if (term->quantityType != QuantifierFixedCount && !term->parentheses.disjunction->m_minimumSize) { |
| Jump pastBreakpoint; |
| pastBreakpoint = branch32(NotEqual, index, Address(stackPointerRegister, term->frameLocation * sizeof(void*))); |
| breakpoint(); |
| pastBreakpoint.link(this); |
| } |
| #endif |
| |
| // If the parenthese are capturing, store the ending index value to the |
| // captures array, offsetting as necessary. |
| // |
| // FIXME: could avoid offsetting this value in JIT code, apply |
| // offsets only afterwards, at the point the results array is |
| // being accessed. |
| if (term->capture() && compileMode == IncludeSubpatterns) { |
| int inputOffset = term->inputPosition - m_checked; |
| if (inputOffset) { |
| move(index, indexTemporary); |
| add32(Imm32(inputOffset), indexTemporary); |
| setSubpatternEnd(indexTemporary, term->parentheses.subpatternId); |
| } else |
| setSubpatternEnd(index, term->parentheses.subpatternId); |
| } |
| |
| // If the parentheses are quantified Greedy then add a label to jump back |
| // to if get a failed match from after the parentheses. For NonGreedy |
| // parentheses, link the jump from before the subpattern to here. |
| if (term->quantityType == QuantifierGreedy) |
| op.m_reentry = label(); |
| else if (term->quantityType == QuantifierNonGreedy) { |
| YarrOp& beginOp = m_ops[op.m_previousOp]; |
| beginOp.m_jumps.link(this); |
| } |
| break; |
| } |
| |
| // OpParenthesesSubpatternTerminalBegin/End |
| case OpParenthesesSubpatternTerminalBegin: { |
| PatternTerm* term = op.m_term; |
| ASSERT(term->quantityType == QuantifierGreedy); |
| ASSERT(term->quantityCount == quantifyInfinite); |
| ASSERT(!term->capture()); |
| |
| // Upon entry set a label to loop back to. |
| op.m_reentry = label(); |
| |
| // Store the start index of the current match; we need to reject zero |
| // length matches. |
| storeToFrame(index, term->frameLocation); |
| break; |
| } |
| case OpParenthesesSubpatternTerminalEnd: { |
| YarrOp& beginOp = m_ops[op.m_previousOp]; |
| #ifndef NDEBUG |
| PatternTerm* term = op.m_term; |
| |
| // Runtime ASSERT to make sure that the nested alternative handled the |
| // "no input consumed" check. |
| Jump pastBreakpoint; |
| pastBreakpoint = branch32(NotEqual, index, Address(stackPointerRegister, term->frameLocation * sizeof(void*))); |
| breakpoint(); |
| pastBreakpoint.link(this); |
| #endif |
| |
| // We know that the match is non-zero, we can accept it and |
| // loop back up to the head of the subpattern. |
| jump(beginOp.m_reentry); |
| |
| // This is the entry point to jump to when we stop matching - we will |
| // do so once the subpattern cannot match any more. |
| op.m_reentry = label(); |
| break; |
| } |
| |
| // OpParentheticalAssertionBegin/End |
| case OpParentheticalAssertionBegin: { |
| PatternTerm* term = op.m_term; |
| |
| // Store the current index - assertions should not update index, so |
| // we will need to restore it upon a successful match. |
| unsigned parenthesesFrameLocation = term->frameLocation; |
| storeToFrame(index, parenthesesFrameLocation); |
| |
| // Check |
| op.m_checkAdjust = m_checked - term->inputPosition; |
| if (op.m_checkAdjust) |
| sub32(Imm32(op.m_checkAdjust), index); |
| |
| m_checked -= op.m_checkAdjust; |
| break; |
| } |
| case OpParentheticalAssertionEnd: { |
| PatternTerm* term = op.m_term; |
| |
| // Restore the input index value. |
| unsigned parenthesesFrameLocation = term->frameLocation; |
| loadFromFrame(parenthesesFrameLocation, index); |
| |
| // If inverted, a successful match of the assertion must be treated |
| // as a failure, so jump to backtracking. |
| if (term->invert()) { |
| op.m_jumps.append(jump()); |
| op.m_reentry = label(); |
| } |
| |
| YarrOp& lastOp = m_ops[op.m_previousOp]; |
| m_checked += lastOp.m_checkAdjust; |
| break; |
| } |
| |
| case OpMatchFailed: |
| #if !WTF_CPU_SPARC |
| removeCallFrame(); |
| #endif |
| #if WTF_CPU_X86_64 |
| move(TrustedImm32(int(WTF::notFound)), returnRegister); |
| #else |
| move(TrustedImmPtr((void*)WTF::notFound), returnRegister); |
| move(TrustedImm32(0), returnRegister2); |
| #endif |
| generateReturn(); |
| break; |
| } |
| |
| ++opIndex; |
| } while (opIndex < m_ops.size()); |
| } |
| |
| void backtrack() |
| { |
| // Backwards generate the backtracking code. |
| size_t opIndex = m_ops.size(); |
| ASSERT(opIndex); |
| |
| do { |
| --opIndex; |
| YarrOp& op = m_ops[opIndex]; |
| switch (op.m_op) { |
| |
| case OpTerm: |
| backtrackTerm(opIndex); |
| break; |
| |
| // OpBodyAlternativeBegin/Next/End |
| // |
| // For each Begin/Next node representing an alternative, we need to decide what to do |
| // in two circumstances: |
| // - If we backtrack back into this node, from within the alternative. |
| // - If the input check at the head of the alternative fails (if this exists). |
| // |
| // We treat these two cases differently since in the former case we have slightly |
| // more information - since we are backtracking out of a prior alternative we know |
| // that at least enough input was available to run it. For example, given the regular |
| // expression /a|b/, if we backtrack out of the first alternative (a failed pattern |
| // character match of 'a'), then we need not perform an additional input availability |
| // check before running the second alternative. |
| // |
| // Backtracking required differs for the last alternative, which in the case of the |
| // repeating set of alternatives must loop. The code generated for the last alternative |
| // will also be used to handle all input check failures from any prior alternatives - |
| // these require similar functionality, in seeking the next available alternative for |
| // which there is sufficient input. |
| // |
| // Since backtracking of all other alternatives simply requires us to link backtracks |
| // to the reentry point for the subsequent alternative, we will only be generating any |
| // code when backtracking the last alternative. |
| case OpBodyAlternativeBegin: |
| case OpBodyAlternativeNext: { |
| PatternAlternative* alternative = op.m_alternative; |
| |
| if (op.m_op == OpBodyAlternativeNext) { |
| PatternAlternative* priorAlternative = m_ops[op.m_previousOp].m_alternative; |
| m_checked += priorAlternative->m_minimumSize; |
| } |
| m_checked -= alternative->m_minimumSize; |
| |
| // Is this the last alternative? If not, then if we backtrack to this point we just |
| // need to jump to try to match the next alternative. |
| if (m_ops[op.m_nextOp].m_op != OpBodyAlternativeEnd) { |
| m_backtrackingState.linkTo(m_ops[op.m_nextOp].m_reentry, this); |
| break; |
| } |
| YarrOp& endOp = m_ops[op.m_nextOp]; |
| |
| YarrOp* beginOp = &op; |
| while (beginOp->m_op != OpBodyAlternativeBegin) { |
| ASSERT(beginOp->m_op == OpBodyAlternativeNext); |
| beginOp = &m_ops[beginOp->m_previousOp]; |
| } |
| |
| bool onceThrough = endOp.m_nextOp == notFound; |
| |
| // First, generate code to handle cases where we backtrack out of an attempted match |
| // of the last alternative. If this is a 'once through' set of alternatives then we |
| // have nothing to do - link this straight through to the End. |
| if (onceThrough) |
| m_backtrackingState.linkTo(endOp.m_reentry, this); |
| else { |
| // If we don't need to move the input poistion, and the pattern has a fixed size |
| // (in which case we omit the store of the start index until the pattern has matched) |
| // then we can just link the backtrack out of the last alternative straight to the |
| // head of the first alternative. |
| if (m_pattern.m_body->m_hasFixedSize |
| && (alternative->m_minimumSize > beginOp->m_alternative->m_minimumSize) |
| && (alternative->m_minimumSize - beginOp->m_alternative->m_minimumSize == 1)) |
| m_backtrackingState.linkTo(beginOp->m_reentry, this); |
| else { |
| // We need to generate a trampoline of code to execute before looping back |
| // around to the first alternative. |
| m_backtrackingState.link(this); |
| |
| // If the pattern size is not fixed, then store the start index, for use if we match. |
| if (!m_pattern.m_body->m_hasFixedSize) { |
| if (alternative->m_minimumSize == 1) |
| setMatchStart(index); |
| else { |
| move(index, regT0); |
| if (alternative->m_minimumSize) |
| sub32(Imm32(alternative->m_minimumSize - 1), regT0); |
| else |
| add32(TrustedImm32(1), regT0); |
| setMatchStart(regT0); |
| } |
| } |
| |
| // Generate code to loop. Check whether the last alternative is longer than the |
| // first (e.g. /a|xy/ or /a|xyz/). |
| if (alternative->m_minimumSize > beginOp->m_alternative->m_minimumSize) { |
| // We want to loop, and increment input position. If the delta is 1, it is |
| // already correctly incremented, if more than one then decrement as appropriate. |
| unsigned delta = alternative->m_minimumSize - beginOp->m_alternative->m_minimumSize; |
| ASSERT(delta); |
| if (delta != 1) |
| sub32(Imm32(delta - 1), index); |
| jump(beginOp->m_reentry); |
| } else { |
| // If the first alternative has minimum size 0xFFFFFFFFu, then there cannot |
| // be sufficent input available to handle this, so just fall through. |
| unsigned delta = beginOp->m_alternative->m_minimumSize - alternative->m_minimumSize; |
| if (delta != 0xFFFFFFFFu) { |
| // We need to check input because we are incrementing the input. |
| add32(Imm32(delta + 1), index); |
| checkInput().linkTo(beginOp->m_reentry, this); |
| } |
| } |
| } |
| } |
| |
| // We can reach this point in the code in two ways: |
| // - Fallthrough from the code above (a repeating alternative backtracked out of its |
| // last alternative, and did not have sufficent input to run the first). |
| // - We will loop back up to the following label when a releating alternative loops, |
| // following a failed input check. |
| // |
| // Either way, we have just failed the input check for the first alternative. |
| Label firstInputCheckFailed(this); |
| |
| // Generate code to handle input check failures from alternatives except the last. |
| // prevOp is the alternative we're handling a bail out from (initially Begin), and |
| // nextOp is the alternative we will be attempting to reenter into. |
| // |
| // We will link input check failures from the forwards matching path back to the code |
| // that can handle them. |
| YarrOp* prevOp = beginOp; |
| YarrOp* nextOp = &m_ops[beginOp->m_nextOp]; |
| while (nextOp->m_op != OpBodyAlternativeEnd) { |
| prevOp->m_jumps.link(this); |
| |
| // We only get here if an input check fails, it is only worth checking again |
| // if the next alternative has a minimum size less than the last. |
| if (prevOp->m_alternative->m_minimumSize > nextOp->m_alternative->m_minimumSize) { |
| // FIXME: if we added an extra label to YarrOp, we could avoid needing to |
| // subtract delta back out, and reduce this code. Should performance test |
| // the benefit of this. |
| unsigned delta = prevOp->m_alternative->m_minimumSize - nextOp->m_alternative->m_minimumSize; |
| sub32(Imm32(delta), index); |
| Jump fail = jumpIfNoAvailableInput(); |
| add32(Imm32(delta), index); |
| jump(nextOp->m_reentry); |
| fail.link(this); |
| } else if (prevOp->m_alternative->m_minimumSize < nextOp->m_alternative->m_minimumSize) |
| add32(Imm32(nextOp->m_alternative->m_minimumSize - prevOp->m_alternative->m_minimumSize), index); |
| prevOp = nextOp; |
| nextOp = &m_ops[nextOp->m_nextOp]; |
| } |
| |
| // We fall through to here if there is insufficient input to run the last alternative. |
| |
| // If there is insufficient input to run the last alternative, then for 'once through' |
| // alternatives we are done - just jump back up into the forwards matching path at the End. |
| if (onceThrough) { |
| op.m_jumps.linkTo(endOp.m_reentry, this); |
| jump(endOp.m_reentry); |
| break; |
| } |
| |
| // For repeating alternatives, link any input check failure from the last alternative to |
| // this point. |
| op.m_jumps.link(this); |
| |
| bool needsToUpdateMatchStart = !m_pattern.m_body->m_hasFixedSize; |
| |
| // Check for cases where input position is already incremented by 1 for the last |
| // alternative (this is particularly useful where the minimum size of the body |
| // disjunction is 0, e.g. /a*|b/). |
| if (needsToUpdateMatchStart && alternative->m_minimumSize == 1) { |
| // index is already incremented by 1, so just store it now! |
| setMatchStart(index); |
| needsToUpdateMatchStart = false; |
| } |
| |
| // Check whether there is sufficient input to loop. Increment the input position by |
| // one, and check. Also add in the minimum disjunction size before checking - there |
| // is no point in looping if we're just going to fail all the input checks around |
| // the next iteration. |
| ASSERT(alternative->m_minimumSize >= m_pattern.m_body->m_minimumSize); |
| if (alternative->m_minimumSize == m_pattern.m_body->m_minimumSize) { |
| // If the last alternative had the same minimum size as the disjunction, |
| // just simply increment input pos by 1, no adjustment based on minimum size. |
| add32(TrustedImm32(1), index); |
| } else { |
| // If the minumum for the last alternative was one greater than than that |
| // for the disjunction, we're already progressed by 1, nothing to do! |
| unsigned delta = (alternative->m_minimumSize - m_pattern.m_body->m_minimumSize) - 1; |
| if (delta) |
| sub32(Imm32(delta), index); |
| } |
| Jump matchFailed = jumpIfNoAvailableInput(); |
| |
| if (needsToUpdateMatchStart) { |
| if (!m_pattern.m_body->m_minimumSize) |
| setMatchStart(index); |
| else { |
| move(index, regT0); |
| sub32(Imm32(m_pattern.m_body->m_minimumSize), regT0); |
| setMatchStart(regT0); |
| } |
| } |
| |
| // Calculate how much more input the first alternative requires than the minimum |
| // for the body as a whole. If no more is needed then we dont need an additional |
| // input check here - jump straight back up to the start of the first alternative. |
| if (beginOp->m_alternative->m_minimumSize == m_pattern.m_body->m_minimumSize) |
| jump(beginOp->m_reentry); |
| else { |
| if (beginOp->m_alternative->m_minimumSize > m_pattern.m_body->m_minimumSize) |
| add32(Imm32(beginOp->m_alternative->m_minimumSize - m_pattern.m_body->m_minimumSize), index); |
| else |
| sub32(Imm32(m_pattern.m_body->m_minimumSize - beginOp->m_alternative->m_minimumSize), index); |
| checkInput().linkTo(beginOp->m_reentry, this); |
| jump(firstInputCheckFailed); |
| } |
| |
| // We jump to here if we iterate to the point that there is insufficient input to |
| // run any matches, and need to return a failure state from JIT code. |
| matchFailed.link(this); |
| |
| #if !WTF_CPU_SPARC |
| removeCallFrame(); |
| #endif |
| #if WTF_CPU_X86_64 |
| move(TrustedImm32(int(WTF::notFound)), returnRegister); |
| #else |
| move(TrustedImmPtr((void*)WTF::notFound), returnRegister); |
| move(TrustedImm32(0), returnRegister2); |
| #endif |
| generateReturn(); |
| break; |
| } |
| case OpBodyAlternativeEnd: { |
| // We should never backtrack back into a body disjunction. |
| ASSERT(m_backtrackingState.isEmpty()); |
| |
| PatternAlternative* priorAlternative = m_ops[op.m_previousOp].m_alternative; |
| m_checked += priorAlternative->m_minimumSize; |
| break; |
| } |
| |
| // OpSimpleNestedAlternativeBegin/Next/End |
| // OpNestedAlternativeBegin/Next/End |
| // |
| // Generate code for when we backtrack back out of an alternative into |
| // a Begin or Next node, or when the entry input count check fails. If |
| // there are more alternatives we need to jump to the next alternative, |
| // if not we backtrack back out of the current set of parentheses. |
| // |
| // In the case of non-simple nested assertions we need to also link the |
| // 'return address' appropriately to backtrack back out into the correct |
| // alternative. |
| case OpSimpleNestedAlternativeBegin: |
| case OpSimpleNestedAlternativeNext: |
| case OpNestedAlternativeBegin: |
| case OpNestedAlternativeNext: { |
| YarrOp& nextOp = m_ops[op.m_nextOp]; |
| bool isBegin = op.m_previousOp == notFound; |
| bool isLastAlternative = nextOp.m_nextOp == notFound; |
| ASSERT(isBegin == (op.m_op == OpSimpleNestedAlternativeBegin || op.m_op == OpNestedAlternativeBegin)); |
| ASSERT(isLastAlternative == (nextOp.m_op == OpSimpleNestedAlternativeEnd || nextOp.m_op == OpNestedAlternativeEnd)); |
| |
| // Treat an input check failure the same as a failed match. |
| m_backtrackingState.append(op.m_jumps); |
| |
| // Set the backtracks to jump to the appropriate place. We may need |
| // to link the backtracks in one of three different way depending on |
| // the type of alternative we are dealing with: |
| // - A single alternative, with no simplings. |
| // - The last alternative of a set of two or more. |
| // - An alternative other than the last of a set of two or more. |
| // |
| // In the case of a single alternative on its own, we don't need to |
| // jump anywhere - if the alternative fails to match we can just |
| // continue to backtrack out of the parentheses without jumping. |
| // |
| // In the case of the last alternative in a set of more than one, we |
| // need to jump to return back out to the beginning. We'll do so by |
| // adding a jump to the End node's m_jumps list, and linking this |
| // when we come to generate the Begin node. For alternatives other |
| // than the last, we need to jump to the next alternative. |
| // |
| // If the alternative had adjusted the input position we must link |
| // backtracking to here, correct, and then jump on. If not we can |
| // link the backtracks directly to their destination. |
| if (op.m_checkAdjust) { |
| // Handle the cases where we need to link the backtracks here. |
| m_backtrackingState.link(this); |
| sub32(Imm32(op.m_checkAdjust), index); |
| if (!isLastAlternative) { |
| // An alternative that is not the last should jump to its successor. |
| jump(nextOp.m_reentry); |
| } else if (!isBegin) { |
| // The last of more than one alternatives must jump back to the beginning. |
| nextOp.m_jumps.append(jump()); |
| } else { |
| // A single alternative on its own can fall through. |
| m_backtrackingState.fallthrough(); |
| } |
| } else { |
| // Handle the cases where we can link the backtracks directly to their destinations. |
| if (!isLastAlternative) { |
| // An alternative that is not the last should jump to its successor. |
| m_backtrackingState.linkTo(nextOp.m_reentry, this); |
| } else if (!isBegin) { |
| // The last of more than one alternatives must jump back to the beginning. |
| m_backtrackingState.takeBacktracksToJumpList(nextOp.m_jumps, this); |
| } |
| // In the case of a single alternative on its own do nothing - it can fall through. |
| } |
| |
| // If there is a backtrack jump from a zero length match link it here. |
| if (op.m_zeroLengthMatch.isSet()) |
| m_backtrackingState.append(op.m_zeroLengthMatch); |
| |
| // At this point we've handled the backtracking back into this node. |
| // Now link any backtracks that need to jump to here. |
| |
| // For non-simple alternatives, link the alternative's 'return address' |
| // so that we backtrack back out into the previous alternative. |
| if (op.m_op == OpNestedAlternativeNext) |
| m_backtrackingState.append(op.m_returnAddress); |
| |
| // If there is more than one alternative, then the last alternative will |
| // have planted a jump to be linked to the end. This jump was added to the |
| // End node's m_jumps list. If we are back at the beginning, link it here. |
| if (isBegin) { |
| YarrOp* endOp = &m_ops[op.m_nextOp]; |
| while (endOp->m_nextOp != notFound) { |
| ASSERT(endOp->m_op == OpSimpleNestedAlternativeNext || endOp->m_op == OpNestedAlternativeNext); |
| endOp = &m_ops[endOp->m_nextOp]; |
| } |
| ASSERT(endOp->m_op == OpSimpleNestedAlternativeEnd || endOp->m_op == OpNestedAlternativeEnd); |
| m_backtrackingState.append(endOp->m_jumps); |
| } |
| |
| if (!isBegin) { |
| YarrOp& lastOp = m_ops[op.m_previousOp]; |
| m_checked += lastOp.m_checkAdjust; |
| } |
| m_checked -= op.m_checkAdjust; |
| break; |
| } |
| case OpSimpleNestedAlternativeEnd: |
| case OpNestedAlternativeEnd: { |
| PatternTerm* term = op.m_term; |
| |
| // If there is a backtrack jump from a zero length match link it here. |
| if (op.m_zeroLengthMatch.isSet()) |
| m_backtrackingState.append(op.m_zeroLengthMatch); |
| |
| // If we backtrack into the end of a simple subpattern do nothing; |
| // just continue through into the last alternative. If we backtrack |
| // into the end of a non-simple set of alterntives we need to jump |
| // to the backtracking return address set up during generation. |
| if (op.m_op == OpNestedAlternativeEnd) { |
| m_backtrackingState.link(this); |
| |
| // Plant a jump to the return address. |
| unsigned parenthesesFrameLocation = term->frameLocation; |
| unsigned alternativeFrameLocation = parenthesesFrameLocation; |
| if (term->quantityType != QuantifierFixedCount) |
| alternativeFrameLocation += YarrStackSpaceForBackTrackInfoParenthesesOnce; |
| loadFromFrameAndJump(alternativeFrameLocation); |
| |
| // Link the DataLabelPtr associated with the end of the last |
| // alternative to this point. |
| m_backtrackingState.append(op.m_returnAddress); |
| } |
| |
| YarrOp& lastOp = m_ops[op.m_previousOp]; |
| m_checked += lastOp.m_checkAdjust; |
| break; |
| } |
| |
| // OpParenthesesSubpatternOnceBegin/End |
| // |
| // When we are backtracking back out of a capturing subpattern we need |
| // to clear the start index in the matches output array, to record that |
| // this subpattern has not been captured. |
| // |
| // When backtracking back out of a Greedy quantified subpattern we need |
| // to catch this, and try running the remainder of the alternative after |
| // the subpattern again, skipping the parentheses. |
| // |
| // Upon backtracking back into a quantified set of parentheses we need to |
| // check whether we were currently skipping the subpattern. If not, we |
| // can backtrack into them, if we were we need to either backtrack back |
| // out of the start of the parentheses, or jump back to the forwards |
| // matching start, depending of whether the match is Greedy or NonGreedy. |
| case OpParenthesesSubpatternOnceBegin: { |
| PatternTerm* term = op.m_term; |
| ASSERT(term->quantityCount == 1); |
| |
| // We only need to backtrack to thispoint if capturing or greedy. |
| if ((term->capture() && compileMode == IncludeSubpatterns) || term->quantityType == QuantifierGreedy) { |
| m_backtrackingState.link(this); |
| |
| // If capturing, clear the capture (we only need to reset start). |
| if (term->capture() && compileMode == IncludeSubpatterns) |
| clearSubpatternStart(term->parentheses.subpatternId); |
| |
| // If Greedy, jump to the end. |
| if (term->quantityType == QuantifierGreedy) { |
| // Clear the flag in the stackframe indicating we ran through the subpattern. |
| unsigned parenthesesFrameLocation = term->frameLocation; |
| storeToFrame(TrustedImm32(-1), parenthesesFrameLocation); |
| // Jump to after the parentheses, skipping the subpattern. |
| jump(m_ops[op.m_nextOp].m_reentry); |
| // A backtrack from after the parentheses, when skipping the subpattern, |
| // will jump back to here. |
| op.m_jumps.link(this); |
| } |
| |
| m_backtrackingState.fallthrough(); |
| } |
| break; |
| } |
| case OpParenthesesSubpatternOnceEnd: { |
| PatternTerm* term = op.m_term; |
| |
| if (term->quantityType != QuantifierFixedCount) { |
| m_backtrackingState.link(this); |
| |
| // Check whether we should backtrack back into the parentheses, or if we |
| // are currently in a state where we had skipped over the subpattern |
| // (in which case the flag value on the stack will be -1). |
| unsigned parenthesesFrameLocation = term->frameLocation; |
| Jump hadSkipped = branch32(Equal, Address(stackPointerRegister, parenthesesFrameLocation * sizeof(void*)), TrustedImm32(-1)); |
| |
| if (term->quantityType == QuantifierGreedy) { |
| // For Greedy parentheses, we skip after having already tried going |
| // through the subpattern, so if we get here we're done. |
| YarrOp& beginOp = m_ops[op.m_previousOp]; |
| beginOp.m_jumps.append(hadSkipped); |
| } else { |
| // For NonGreedy parentheses, we try skipping the subpattern first, |
| // so if we get here we need to try running through the subpattern |
| // next. Jump back to the start of the parentheses in the forwards |
| // matching path. |
| ASSERT(term->quantityType == QuantifierNonGreedy); |
| YarrOp& beginOp = m_ops[op.m_previousOp]; |
| hadSkipped.linkTo(beginOp.m_reentry, this); |
| } |
| |
| m_backtrackingState.fallthrough(); |
| } |
| |
| m_backtrackingState.append(op.m_jumps); |
| break; |
| } |
| |
| // OpParenthesesSubpatternTerminalBegin/End |
| // |
| // Terminal subpatterns will always match - there is nothing after them to |
| // force a backtrack, and they have a minimum count of 0, and as such will |
| // always produce an acceptable result. |
| case OpParenthesesSubpatternTerminalBegin: { |
| // We will backtrack to this point once the subpattern cannot match any |
| // more. Since no match is accepted as a successful match (we are Greedy |
| // quantified with a minimum of zero) jump back to the forwards matching |
| // path at the end. |
| YarrOp& endOp = m_ops[op.m_nextOp]; |
| m_backtrackingState.linkTo(endOp.m_reentry, this); |
| break; |
| } |
| case OpParenthesesSubpatternTerminalEnd: |
| // We should never be backtracking to here (hence the 'terminal' in the name). |
| ASSERT(m_backtrackingState.isEmpty()); |
| m_backtrackingState.append(op.m_jumps); |
| break; |
| |
| // OpParentheticalAssertionBegin/End |
| case OpParentheticalAssertionBegin: { |
| PatternTerm* term = op.m_term; |
| YarrOp& endOp = m_ops[op.m_nextOp]; |
| |
| // We need to handle the backtracks upon backtracking back out |
| // of a parenthetical assertion if either we need to correct |
| // the input index, or the assertion was inverted. |
| if (op.m_checkAdjust || term->invert()) { |
| m_backtrackingState.link(this); |
| |
| if (op.m_checkAdjust) |
| add32(Imm32(op.m_checkAdjust), index); |
| |
| // In an inverted assertion failure to match the subpattern |
| // is treated as a successful match - jump to the end of the |
| // subpattern. We already have adjusted the input position |
| // back to that before the assertion, which is correct. |
| if (term->invert()) |
| jump(endOp.m_reentry); |
| |
| m_backtrackingState.fallthrough(); |
| } |
| |
| // The End node's jump list will contain any backtracks into |
| // the end of the assertion. Also, if inverted, we will have |
| // added the failure caused by a successful match to this. |
| m_backtrackingState.append(endOp.m_jumps); |
| |
| m_checked += op.m_checkAdjust; |
| break; |
| } |
| case OpParentheticalAssertionEnd: { |
| // FIXME: We should really be clearing any nested subpattern |
| // matches on bailing out from after the pattern. Firefox has |
| // this bug too (presumably because they use YARR!) |
| |
| // Never backtrack into an assertion; later failures bail to before the begin. |
| m_backtrackingState.takeBacktracksToJumpList(op.m_jumps, this); |
| |
| YarrOp& lastOp = m_ops[op.m_previousOp]; |
| m_checked -= lastOp.m_checkAdjust; |
| break; |
| } |
| |
| case OpMatchFailed: |
| break; |
| } |
| |
| } while (opIndex); |
| } |
| |
| // Compilation methods: |
| // ==================== |
| |
| // opCompileParenthesesSubpattern |
| // Emits ops for a subpattern (set of parentheses). These consist |
| // of a set of alternatives wrapped in an outer set of nodes for |
| // the parentheses. |
| // Supported types of parentheses are 'Once' (quantityCount == 1) |
| // and 'Terminal' (non-capturing parentheses quantified as greedy |
| // and infinite). |
| // Alternatives will use the 'Simple' set of ops if either the |
| // subpattern is terminal (in which case we will never need to |
| // backtrack), or if the subpattern only contains one alternative. |
| void opCompileParenthesesSubpattern(PatternTerm* term) |
| { |
| YarrOpCode parenthesesBeginOpCode; |
| YarrOpCode parenthesesEndOpCode; |
| YarrOpCode alternativeBeginOpCode = OpSimpleNestedAlternativeBegin; |
| YarrOpCode alternativeNextOpCode = OpSimpleNestedAlternativeNext; |
| YarrOpCode alternativeEndOpCode = OpSimpleNestedAlternativeEnd; |
| |
| // We can currently only compile quantity 1 subpatterns that are |
| // not copies. We generate a copy in the case of a range quantifier, |
| // e.g. /(?:x){3,9}/, or /(?:x)+/ (These are effectively expanded to |
| // /(?:x){3,3}(?:x){0,6}/ and /(?:x)(?:x)*/ repectively). The problem |
| // comes where the subpattern is capturing, in which case we would |
| // need to restore the capture from the first subpattern upon a |
| // failure in the second. |
| if (term->quantityCount == 1 && !term->parentheses.isCopy) { |
| // Select the 'Once' nodes. |
| parenthesesBeginOpCode = OpParenthesesSubpatternOnceBegin; |
| parenthesesEndOpCode = OpParenthesesSubpatternOnceEnd; |
| |
| // If there is more than one alternative we cannot use the 'simple' nodes. |
| if (term->parentheses.disjunction->m_alternatives.size() != 1) { |
| alternativeBeginOpCode = OpNestedAlternativeBegin; |
| alternativeNextOpCode = OpNestedAlternativeNext; |
| alternativeEndOpCode = OpNestedAlternativeEnd; |
| } |
| } else if (term->parentheses.isTerminal) { |
| // Terminal groups are optimized on the assumption that matching will never |
| // backtrack into the terminal group. But this is false if there is more |
| // than one alternative and one of the alternatives can match empty. In that |
| // case, the empty match is counted as a failure, so we would need to backtrack. |
| // The backtracking code doesn't handle this case correctly, so we fall back |
| // to the interpreter. |
| Vector<PatternAlternative*>& alternatives = term->parentheses.disjunction->m_alternatives; |
| if (alternatives.size() != 1) { |
| for (unsigned i = 0; i < alternatives.size(); ++i) { |
| if (alternatives[i]->m_minimumSize == 0) { |
| m_shouldFallBack = true; |
| return; |
| } |
| } |
| } |
| |
| // Select the 'Terminal' nodes. |
| parenthesesBeginOpCode = OpParenthesesSubpatternTerminalBegin; |
| parenthesesEndOpCode = OpParenthesesSubpatternTerminalEnd; |
| } else { |
| // This subpattern is not supported by the JIT. |
| m_shouldFallBack = true; |
| return; |
| } |
| |
| size_t parenBegin = m_ops.size(); |
| m_ops.append(parenthesesBeginOpCode); |
| |
| m_ops.append(alternativeBeginOpCode); |
| m_ops.last().m_previousOp = notFound; |
| m_ops.last().m_term = term; |
| Vector<PatternAlternative*>& alternatives = term->parentheses.disjunction->m_alternatives; |
| for (unsigned i = 0; i < alternatives.size(); ++i) { |
| size_t lastOpIndex = m_ops.size() - 1; |
| |
| PatternAlternative* nestedAlternative = alternatives[i]; |
| opCompileAlternative(nestedAlternative); |
| |
| size_t thisOpIndex = m_ops.size(); |
| m_ops.append(YarrOp(alternativeNextOpCode)); |
| |
| YarrOp& lastOp = m_ops[lastOpIndex]; |
| YarrOp& thisOp = m_ops[thisOpIndex]; |
| |
| lastOp.m_alternative = nestedAlternative; |
| lastOp.m_nextOp = thisOpIndex; |
| thisOp.m_previousOp = lastOpIndex; |
| thisOp.m_term = term; |
| } |
| YarrOp& lastOp = m_ops.last(); |
| ASSERT(lastOp.m_op == alternativeNextOpCode); |
| lastOp.m_op = alternativeEndOpCode; |
| lastOp.m_alternative = 0; |
| lastOp.m_nextOp = notFound; |
| |
| size_t parenEnd = m_ops.size(); |
| m_ops.append(parenthesesEndOpCode); |
| |
| m_ops[parenBegin].m_term = term; |
| m_ops[parenBegin].m_previousOp = notFound; |
| m_ops[parenBegin].m_nextOp = parenEnd; |
| m_ops[parenEnd].m_term = term; |
| m_ops[parenEnd].m_previousOp = parenBegin; |
| m_ops[parenEnd].m_nextOp = notFound; |
| } |
| |
| // opCompileParentheticalAssertion |
| // Emits ops for a parenthetical assertion. These consist of an |
| // OpSimpleNestedAlternativeBegin/Next/End set of nodes wrapping |
| // the alternatives, with these wrapped by an outer pair of |
| // OpParentheticalAssertionBegin/End nodes. |
| // We can always use the OpSimpleNestedAlternative nodes in the |
| // case of parenthetical assertions since these only ever match |
| // once, and will never backtrack back into the assertion. |
| void opCompileParentheticalAssertion(PatternTerm* term) |
| { |
| size_t parenBegin = m_ops.size(); |
| m_ops.append(OpParentheticalAssertionBegin); |
| |
| m_ops.append(OpSimpleNestedAlternativeBegin); |
| m_ops.last().m_previousOp = notFound; |
| m_ops.last().m_term = term; |
| Vector<PatternAlternative*>& alternatives = term->parentheses.disjunction->m_alternatives; |
| for (unsigned i = 0; i < alternatives.size(); ++i) { |
| size_t lastOpIndex = m_ops.size() - 1; |
| |
| PatternAlternative* nestedAlternative = alternatives[i]; |
| opCompileAlternative(nestedAlternative); |
| |
| size_t thisOpIndex = m_ops.size(); |
| m_ops.append(YarrOp(OpSimpleNestedAlternativeNext)); |
| |
| YarrOp& lastOp = m_ops[lastOpIndex]; |
| YarrOp& thisOp = m_ops[thisOpIndex]; |
| |
| lastOp.m_alternative = nestedAlternative; |
| lastOp.m_nextOp = thisOpIndex; |
| thisOp.m_previousOp = lastOpIndex; |
| thisOp.m_term = term; |
| } |
| YarrOp& lastOp = m_ops.last(); |
| ASSERT(lastOp.m_op == OpSimpleNestedAlternativeNext); |
| lastOp.m_op = OpSimpleNestedAlternativeEnd; |
| lastOp.m_alternative = 0; |
| lastOp.m_nextOp = notFound; |
| |
| size_t parenEnd = m_ops.size(); |
| m_ops.append(OpParentheticalAssertionEnd); |
| |
| m_ops[parenBegin].m_term = term; |
| m_ops[parenBegin].m_previousOp = notFound; |
| m_ops[parenBegin].m_nextOp = parenEnd; |
| m_ops[parenEnd].m_term = term; |
| m_ops[parenEnd].m_previousOp = parenBegin; |
| m_ops[parenEnd].m_nextOp = notFound; |
| } |
| |
| // opCompileAlternative |
| // Called to emit nodes for all terms in an alternative. |
| void opCompileAlternative(PatternAlternative* alternative) |
| { |
| optimizeAlternative(alternative); |
| |
| for (unsigned i = 0; i < alternative->m_terms.size(); ++i) { |
| PatternTerm* term = &alternative->m_terms[i]; |
| |
| switch (term->type) { |
| case PatternTerm::TypeParenthesesSubpattern: |
| opCompileParenthesesSubpattern(term); |
| break; |
| |
| case PatternTerm::TypeParentheticalAssertion: |
| opCompileParentheticalAssertion(term); |
| break; |
| |
| default: |
| m_ops.append(term); |
| } |
| } |
| } |
| |
| // opCompileBody |
| // This method compiles the body disjunction of the regular expression. |
| // The body consists of two sets of alternatives - zero or more 'once |
| // through' (BOL anchored) alternatives, followed by zero or more |
| // repeated alternatives. |
| // For each of these two sets of alteratives, if not empty they will be |
| // wrapped in a set of OpBodyAlternativeBegin/Next/End nodes (with the |
| // 'begin' node referencing the first alternative, and 'next' nodes |
| // referencing any further alternatives. The begin/next/end nodes are |
| // linked together in a doubly linked list. In the case of repeating |
| // alternatives, the end node is also linked back to the beginning. |
| // If no repeating alternatives exist, then a OpMatchFailed node exists |
| // to return the failing result. |
| void opCompileBody(PatternDisjunction* disjunction) |
| { |
| Vector<PatternAlternative*>& alternatives = disjunction->m_alternatives; |
| size_t currentAlternativeIndex = 0; |
| |
| // Emit the 'once through' alternatives. |
| if (alternatives.size() && alternatives[0]->onceThrough()) { |
| m_ops.append(YarrOp(OpBodyAlternativeBegin)); |
| m_ops.last().m_previousOp = notFound; |
| |
| do { |
| size_t lastOpIndex = m_ops.size() - 1; |
| PatternAlternative* alternative = alternatives[currentAlternativeIndex]; |
| opCompileAlternative(alternative); |
| |
| size_t thisOpIndex = m_ops.size(); |
| m_ops.append(YarrOp(OpBodyAlternativeNext)); |
| |
| YarrOp& lastOp = m_ops[lastOpIndex]; |
| YarrOp& thisOp = m_ops[thisOpIndex]; |
| |
| lastOp.m_alternative = alternative; |
| lastOp.m_nextOp = thisOpIndex; |
| thisOp.m_previousOp = lastOpIndex; |
| |
| ++currentAlternativeIndex; |
| } while (currentAlternativeIndex < alternatives.size() && alternatives[currentAlternativeIndex]->onceThrough()); |
| |
| YarrOp& lastOp = m_ops.last(); |
| |
| ASSERT(lastOp.m_op == OpBodyAlternativeNext); |
| lastOp.m_op = OpBodyAlternativeEnd; |
| lastOp.m_alternative = 0; |
| lastOp.m_nextOp = notFound; |
| } |
| |
| if (currentAlternativeIndex == alternatives.size()) { |
| m_ops.append(YarrOp(OpMatchFailed)); |
| return; |
| } |
| |
| // Emit the repeated alternatives. |
| size_t repeatLoop = m_ops.size(); |
| m_ops.append(YarrOp(OpBodyAlternativeBegin)); |
| m_ops.last().m_previousOp = notFound; |
| do { |
| size_t lastOpIndex = m_ops.size() - 1; |
| PatternAlternative* alternative = alternatives[currentAlternativeIndex]; |
| ASSERT(!alternative->onceThrough()); |
| opCompileAlternative(alternative); |
| |
| size_t thisOpIndex = m_ops.size(); |
| m_ops.append(YarrOp(OpBodyAlternativeNext)); |
| |
| YarrOp& lastOp = m_ops[lastOpIndex]; |
| YarrOp& thisOp = m_ops[thisOpIndex]; |
| |
| lastOp.m_alternative = alternative; |
| lastOp.m_nextOp = thisOpIndex; |
| thisOp.m_previousOp = lastOpIndex; |
| |
| ++currentAlternativeIndex; |
| } while (currentAlternativeIndex < alternatives.size()); |
| YarrOp& lastOp = m_ops.last(); |
| ASSERT(lastOp.m_op == OpBodyAlternativeNext); |
| lastOp.m_op = OpBodyAlternativeEnd; |
| lastOp.m_alternative = 0; |
| lastOp.m_nextOp = repeatLoop; |
| } |
| |
| void generateEnter() |
| { |
| #if WTF_CPU_X86_64 |
| push(X86Registers::ebp); |
| move(stackPointerRegister, X86Registers::ebp); |
| push(X86Registers::ebx); |
| // The ABI doesn't guarantee the upper bits are zero on unsigned arguments, so clear them ourselves. |
| zeroExtend32ToPtr(index, index); |
| zeroExtend32ToPtr(length, length); |
| #elif WTF_CPU_X86 |
| push(X86Registers::ebp); |
| move(stackPointerRegister, X86Registers::ebp); |
| // TODO: do we need spill registers to fill the output pointer if there are no sub captures? |
| push(X86Registers::ebx); |
| push(X86Registers::edi); |
| push(X86Registers::esi); |
| // load output into edi (2 = saved ebp + return address). |
| # if WTF_COMPILER_MSVC || WTF_COMPILER_SUNCC |
| loadPtr(Address(X86Registers::ebp, 2 * sizeof(void*)), input); |
| loadPtr(Address(X86Registers::ebp, 3 * sizeof(void*)), index); |
| loadPtr(Address(X86Registers::ebp, 4 * sizeof(void*)), length); |
| if (compileMode == IncludeSubpatterns) |
| loadPtr(Address(X86Registers::ebp, 5 * sizeof(void*)), output); |
| # else |
| if (compileMode == IncludeSubpatterns) |
| loadPtr(Address(X86Registers::ebp, 2 * sizeof(void*)), output); |
| # endif |
| #elif WTF_CPU_ARM |
| push(ARMRegisters::r4); |
| push(ARMRegisters::r5); |
| push(ARMRegisters::r6); |
| # if WTF_CPU_ARM_TRADITIONAL |
| push(ARMRegisters::r8); // scratch register |
| # endif |
| if (compileMode == IncludeSubpatterns) |
| move(ARMRegisters::r3, output); |
| #elif WTF_CPU_SH4 |
| push(SH4Registers::r11); |
| push(SH4Registers::r13); |
| #elif WTF_CPU_SPARC |
| save(Imm32(-m_pattern.m_body->m_callFrameSize * sizeof(void*))); |
| #elif WTF_CPU_MIPS |
| // Do nothing. |
| #endif |
| } |
| |
| void generateReturn() |
| { |
| #if WTF_CPU_X86_64 |
| pop(X86Registers::ebx); |
| pop(X86Registers::ebp); |
| #elif WTF_CPU_X86 |
| pop(X86Registers::esi); |
| pop(X86Registers::edi); |
| pop(X86Registers::ebx); |
| pop(X86Registers::ebp); |
| #elif WTF_CPU_ARM |
| # if WTF_CPU_ARM_TRADITIONAL |
| pop(ARMRegisters::r8); // scratch register |
| # endif |
| pop(ARMRegisters::r6); |
| pop(ARMRegisters::r5); |
| pop(ARMRegisters::r4); |
| #elif WTF_CPU_SH4 |
| pop(SH4Registers::r13); |
| pop(SH4Registers::r11); |
| #elif WTF_CPU_SPARC |
| ret_and_restore(); |
| return; |
| #elif WTF_CPU_MIPS |
| // Do nothing |
| #endif |
| ret(); |
| } |
| |
| public: |
| YarrGenerator(YarrPattern& pattern, YarrCharSize charSize) |
| : m_pattern(pattern) |
| , m_charSize(charSize) |
| , m_charScale(m_charSize == Char8 ? TimesOne: TimesTwo) |
| , m_shouldFallBack(false) |
| , m_checked(0) |
| { |
| } |
| |
| void compile(JSGlobalData* globalData, YarrCodeBlock& jitObject) |
| { |
| generateEnter(); |
| |
| Jump hasInput = checkInput(); |
| #if WTF_CPU_X86_64 |
| move(TrustedImm32(int(WTF::notFound)), returnRegister); |
| #else |
| move(TrustedImmPtr((void*)WTF::notFound), returnRegister); |
| move(TrustedImm32(0), returnRegister2); |
| #endif |
| generateReturn(); |
| hasInput.link(this); |
| |
| if (compileMode == IncludeSubpatterns) { |
| for (unsigned i = 0; i < m_pattern.m_numSubpatterns + 1; ++i) |
| store32(TrustedImm32(-1), Address(output, (i << 1) * sizeof(int))); |
| } |
| |
| if (!m_pattern.m_body->m_hasFixedSize) |
| setMatchStart(index); |
| |
| initCallFrame(); |
| |
| // Compile the pattern to the internal 'YarrOp' representation. |
| opCompileBody(m_pattern.m_body); |
| |
| // If we encountered anything we can't handle in the JIT code |
| // (e.g. backreferences) then return early. |
| if (m_shouldFallBack) { |
| jitObject.setFallBack(true); |
| return; |
| } |
| |
| generate(); |
| backtrack(); |
| |
| // Link & finalize the code. |
| // XXX yarr-oom |
| ExecutablePool *pool; |
| bool ok; |
| LinkBuffer linkBuffer(this, globalData->regexAllocator, &pool, &ok, REGEXP_CODE); |
| m_backtrackingState.linkDataLabels(linkBuffer); |
| |
| if (compileMode == MatchOnly) { |
| #if YARR_8BIT_CHAR_SUPPORT |
| if (m_charSize == Char8) |
| jitObject.set8BitCodeMatchOnly(linkBuffer.finalizeCode()); |
| else |
| #endif |
| jitObject.set16BitCodeMatchOnly(linkBuffer.finalizeCode()); |
| } else { |
| #if YARR_8BIT_CHAR_SUPPORT |
| if (m_charSize == Char8) |
| jitObject.set8BitCode(linkBuffer.finalizeCode()); |
| else |
| #endif |
| jitObject.set16BitCode(linkBuffer.finalizeCode()); |
| } |
| jitObject.setFallBack(m_shouldFallBack); |
| } |
| |
| private: |
| YarrPattern& m_pattern; |
| |
| YarrCharSize m_charSize; |
| |
| Scale m_charScale; |
| |
| // Used to detect regular expression constructs that are not currently |
| // supported in the JIT; fall back to the interpreter when this is detected. |
| bool m_shouldFallBack; |
| |
| // The regular expression expressed as a linear sequence of operations. |
| Vector<YarrOp, 128> m_ops; |
| |
| // This records the current input offset being applied due to the current |
| // set of alternatives we are nested within. E.g. when matching the |
| // character 'b' within the regular expression /abc/, we will know that |
| // the minimum size for the alternative is 3, checked upon entry to the |
| // alternative, and that 'b' is at offset 1 from the start, and as such |
| // when matching 'b' we need to apply an offset of -2 to the load. |
| // |
| // FIXME: This should go away. Rather than tracking this value throughout |
| // code generation, we should gather this information up front & store it |
| // on the YarrOp structure. |
| int m_checked; |
| |
| // This class records state whilst generating the backtracking path of code. |
| BacktrackingState m_backtrackingState; |
| }; |
| |
| void jitCompile(YarrPattern& pattern, YarrCharSize charSize, JSGlobalData* globalData, YarrCodeBlock& jitObject, YarrJITCompileMode mode) |
| { |
| if (mode == MatchOnly) |
| YarrGenerator<MatchOnly>(pattern, charSize).compile(globalData, jitObject); |
| else |
| YarrGenerator<IncludeSubpatterns>(pattern, charSize).compile(globalData, jitObject); |
| } |
| |
| }} |
| |
| #endif |