Refactoring of RegExp interface to better support calling several times in a row.

Review URL: http://codereview.chromium.org/1114001

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@4190 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/arm/regexp-macro-assembler-arm.cc

@@ -648,16 +648,17 @@ Handle<Object> RegExpMacroAssemblerARM::GetCode(Handle<String> source) {
   __ ldr(r0, MemOperand(frame_pointer(), kInputStart));
   // Find negative length (offset of start relative to end).
   __ sub(current_input_offset(), r0, end_of_input_address());
-  // Set r0 to address of char before start of input
+  // Set r0 to address of char before start of the input string
   // (effectively string position -1).
+  __ ldr(r1, MemOperand(frame_pointer(), kStartIndex));
   __ sub(r0, current_input_offset(), Operand(char_size()));
+  __ sub(r0, r0, Operand(r1, LSL, (mode_ == UC16) ? 1 : 0));
   // Store this value in a local variable, for use when clearing
   // position registers.
   __ str(r0, MemOperand(frame_pointer(), kInputStartMinusOne));
 
   // Determine whether the start index is zero, that is at the start of the
   // string, and store that value in a local variable.
-  __ ldr(r1, MemOperand(frame_pointer(), kStartIndex));
   __ tst(r1, Operand(r1));
   __ mov(r1, Operand(1), LeaveCC, eq);
   __ mov(r1, Operand(0), LeaveCC, ne);
@@ -700,12 +701,15 @@ Handle<Object> RegExpMacroAssemblerARM::GetCode(Handle<String> source) {
       // copy captures to output
       __ ldr(r1, MemOperand(frame_pointer(), kInputStart));
       __ ldr(r0, MemOperand(frame_pointer(), kRegisterOutput));
+      __ ldr(r2, MemOperand(frame_pointer(), kStartIndex));
       __ sub(r1, end_of_input_address(), r1);
       // r1 is length of input in bytes.
       if (mode_ == UC16) {
         __ mov(r1, Operand(r1, LSR, 1));
       }
       // r1 is length of input in characters.
+      __ add(r1, r1, Operand(r2));
+      // r1 is length of string in characters.
 
       ASSERT_EQ(0, num_saved_registers_ % 2);
       // Always an even number of capture registers. This allows us to

src/ia32/codegen-ia32.cc

@@ -10584,15 +10584,7 @@ void RegExpExecStub::Generate(MacroAssembler* masm) {
   __ j(negative, &done);
   // Read the value from the static offsets vector buffer.
   __ mov(edi, Operand(ecx, edx, times_int_size, 0));
-  // Perform explicit shift
-  ASSERT_EQ(0, kSmiTag);
-  __ shl(edi, kSmiTagSize);
-  // Add previous index (from its stack slot) if value is not negative.
-  Label capture_negative;
-  // Carry flag set by shift above.
-  __ j(negative, &capture_negative, not_taken);
-  __ add(edi, Operand(eax));  // Add previous index (adding smi to smi).
-  __ bind(&capture_negative);
+  __ SmiTag(edi);
   // Store the smi value in the last match info.
   __ mov(FieldOperand(ebx,
                       edx,

src/ia32/macro-assembler-ia32.h

@@ -182,7 +182,8 @@ class MacroAssembler: public Assembler {
   // Smi tagging support.
   void SmiTag(Register reg) {
     ASSERT(kSmiTag == 0);
-    shl(reg, kSmiTagSize);
+    ASSERT(kSmiTagSize == 1);
+    add(reg, Operand(reg));
   }
   void SmiUntag(Register reg) {
     sar(reg, kSmiTagSize);

src/ia32/regexp-macro-assembler-ia32.cc

@@ -653,6 +653,8 @@ Handle<Object> RegExpMacroAssemblerIA32::GetCode(Handle<String> source) {
   __ j(not_zero, &exit_label_);
 
   __ bind(&stack_ok);
+  // Load start index for later use.
+  __ mov(ebx, Operand(ebp, kStartIndex));
 
   // Allocate space on stack for registers.
   __ sub(Operand(esp), Immediate(num_registers_ * kPointerSize));
@@ -662,17 +664,23 @@ Handle<Object> RegExpMacroAssemblerIA32::GetCode(Handle<String> source) {
   __ mov(edi, Operand(ebp, kInputStart));
   // Set up edi to be negative offset from string end.
   __ sub(edi, Operand(esi));
-  // Set eax to address of char before start of input
+
+  // Set eax to address of char before start of the string.
   // (effectively string position -1).
-  __ lea(eax, Operand(edi, -char_size()));
+  __ neg(ebx);
+  if (mode_ == UC16) {
+    __ lea(eax, Operand(edi, ebx, times_2, -char_size()));
+  } else {
+    __ lea(eax, Operand(edi, ebx, times_1, -char_size()));
+  }
   // Store this value in a local variable, for use when clearing
   // position registers.
   __ mov(Operand(ebp, kInputStartMinusOne), eax);
 
   // Determine whether the start index is zero, that is at the start of the
   // string, and store that value in a local variable.
-  __ mov(ebx, Operand(ebp, kStartIndex));
   __ xor_(Operand(ecx), ecx);  // setcc only operates on cl (lower byte of ecx).
+  // Register ebx still holds -stringIndex.
   __ test(ebx, Operand(ebx));
   __ setcc(zero, ecx);  // 1 if 0 (start of string), 0 if positive.
   __ mov(Operand(ebp, kAtStart), ecx);
@@ -721,10 +729,17 @@ Handle<Object> RegExpMacroAssemblerIA32::GetCode(Handle<String> source) {
       // copy captures to output
       __ mov(ebx, Operand(ebp, kRegisterOutput));
       __ mov(ecx, Operand(ebp, kInputEnd));
+      __ mov(edx, Operand(ebp, kStartIndex));
       __ sub(ecx, Operand(ebp, kInputStart));
+      if (mode_ == UC16) {
+        __ lea(ecx, Operand(ecx, edx, times_2, 0));
+      } else {
+        __ add(ecx, Operand(edx));
+      }
       for (int i = 0; i < num_saved_registers_; i++) {
         __ mov(eax, register_location(i));
-        __ add(eax, Operand(ecx));  // Convert to index from start, not end.
+        // Convert to index from start of string, not end.
+        __ add(eax, Operand(ecx));
         if (mode_ == UC16) {
           __ sar(eax, 1);  // Convert byte index to character index.
         }

src/jsregexp.h

@@ -77,7 +77,7 @@ class RegExpImpl {
                              Handle<JSArray> lastMatchInfo);
 
   // Prepares a JSRegExp object with Irregexp-specific data.
-  static void IrregexpPrepare(Handle<JSRegExp> re,
+  static void IrregexpInitialize(Handle<JSRegExp> re,
                                  Handle<String> pattern,
                                  JSRegExp::Flags flags,
                                  int capture_register_count);
@@ -93,6 +93,29 @@ class RegExpImpl {
                                  int index,
                                  Handle<JSArray> lastMatchInfo);
 
+  enum IrregexpResult { RE_FAILURE = 0, RE_SUCCESS = 1, RE_EXCEPTION = -1 };
+
+  // Prepare a RegExp for being executed one or more times (using
+  // IrregexpExecOnce) on the subject.
+  // This ensures that the regexp is compiled for the subject, and that
+  // the subject is flat.
+  // Returns the number of integer spaces required by IrregexpExecOnce
+  // as its "registers" argument. If the regexp cannot be compiled,
+  // an exception is set as pending, and this function returns negative.
+  static int IrregexpPrepare(Handle<JSRegExp> regexp,
+                             Handle<String> subject);
+
+  // Execute a regular expression once on the subject, starting from
+  // character "index".
+  // If successful, returns RE_SUCCESS and set the capture positions
+  // in the first registers.
+  // If matching fails, returns RE_FAILURE.
+  // If execution fails, sets a pending exception and returns RE_EXCEPTION.
+  static IrregexpResult IrregexpExecOnce(Handle<JSRegExp> regexp,
+                                         Handle<String> subject,
+                                         int index,
+                                         Vector<int32_t> registers);
+
   // Execute an Irregexp bytecode pattern.
   // On a successful match, the result is a JSArray containing
   // captured positions. On a failure, the result is the null value.

src/x64/codegen-x64.cc

@@ -7182,12 +7182,6 @@ void RegExpExecStub::Generate(MacroAssembler* masm) {
   // Read the value from the static offsets vector buffer and make it a smi.
   __ movl(rdi, Operand(rcx, rdx, times_int_size, 0));
   __ Integer32ToSmi(rdi, rdi, &runtime);
-  // Add previous index (from its stack slot) if value is not negative.
-  Label capture_negative;
-  // Negative flag set by smi convertion above.
-  __ j(negative, &capture_negative);
-  __ SmiAdd(rdi, rdi, rax, &runtime);  // Add previous index.
-  __ bind(&capture_negative);
   // Store the smi value in the last match info.
   __ movq(FieldOperand(rbx,
                        rdx,

src/x64/regexp-macro-assembler-x64.cc

@@ -711,9 +711,15 @@ Handle<Object> RegExpMacroAssemblerX64::GetCode(Handle<String> source) {
   __ movq(rdi, Operand(rbp, kInputStart));
   // Set up rdi to be negative offset from string end.
   __ subq(rdi, rsi);
-  // Set rax to address of char before start of input
+  // Set rax to address of char before start of the string
   // (effectively string position -1).
-  __ lea(rax, Operand(rdi, -char_size()));
+  __ movq(rbx, Operand(rbp, kStartIndex));
+  __ neg(rbx);
+  if (mode_ == UC16) {
+    __ lea(rax, Operand(rdi, rbx, times_2, -char_size()));
+  } else {
+    __ lea(rax, Operand(rdi, rbx, times_1, -char_size()));
+  }
   // Store this value in a local variable, for use when clearing
   // position registers.
   __ movq(Operand(rbp, kInputStartMinusOne), rax);
@@ -770,9 +776,15 @@ Handle<Object> RegExpMacroAssemblerX64::GetCode(Handle<String> source) {
     __ bind(&success_label_);
     if (num_saved_registers_ > 0) {
       // copy captures to output
+      __ movq(rdx, Operand(rbp, kStartIndex));
       __ movq(rbx, Operand(rbp, kRegisterOutput));
       __ movq(rcx, Operand(rbp, kInputEnd));
       __ subq(rcx, Operand(rbp, kInputStart));
+      if (mode_ == UC16) {
+        __ lea(rcx, Operand(rcx, rdx, times_2, 0));
+      } else {
+        __ addq(rcx, rdx);
+      }
       for (int i = 0; i < num_saved_registers_; i++) {
         __ movq(rax, register_location(i));
         __ addq(rax, rcx);  // Convert to index from start, not end.