Bug 1026438 part 9 - Make irregexp CheckNotBackReferenceIgnoreCase work with Latin1 strings. r=bhackett

js/src/irregexp/NativeRegExpMacroAssembler.cpp

@@ -729,7 +729,69 @@ NativeRegExpMacroAssembler::CheckNotBackReferenceIgnoreCase(int start_reg, Label
     masm.branchPtr(Assembler::GreaterThan, temp0, ImmWord(0), BranchOrBacktrack(on_no_match));
 
     if (mode_ == ASCII) {
-        MOZ_ASSUME_UNREACHABLE("Ascii case not implemented");
+        Label success, fail;
+
+        // Save register contents to make the registers available below. After
+        // this, the temp0, temp2, and current_position registers are available.
+        masm.push(current_position);
+
+        masm.addPtr(input_end_pointer, current_character); // Start of capture.
+        masm.addPtr(input_end_pointer, current_position); // Start of text to match against capture.
+        masm.addPtr(current_position, temp1); // End of text to match against capture.
+
+        Label loop, loop_increment;
+        masm.bind(&loop);
+        masm.load8ZeroExtend(Address(current_position, 0), temp0);
+        masm.load8ZeroExtend(Address(current_character, 0), temp2);
+        masm.branch32(Assembler::Equal, temp0, temp2, &loop_increment);
+
+        // Mismatch, try case-insensitive match (converting letters to lower-case).
+        masm.or32(Imm32(0x20), temp0); // Convert match character to lower-case.
+
+        // Is temp0 a lowercase letter?
+        Label convert_capture;
+        masm.computeEffectiveAddress(Address(temp0, -'a'), temp2);
+        masm.branch32(Assembler::BelowOrEqual, temp2, Imm32(static_cast<int32_t>('z' - 'a')),
+                      &convert_capture);
+
+        // Latin-1: Check for values in range [224,254] but not 247.
+        masm.sub32(Imm32(224 - 'a'), temp2);
+        masm.branch32(Assembler::Above, temp2, Imm32(254 - 224), &fail);
+
+        // Check for 247.
+        masm.branch32(Assembler::Equal, temp2, Imm32(247 - 224), &fail);
+
+        masm.bind(&convert_capture);
+
+        // Also convert capture character.
+        masm.load8ZeroExtend(Address(current_character, 0), temp2);
+        masm.or32(Imm32(0x20), temp2);
+
+        masm.branch32(Assembler::NotEqual, temp0, temp2, &fail);
+
+        masm.bind(&loop_increment);
+
+        // Increment pointers into match and capture strings.
+        masm.addPtr(Imm32(1), current_character);
+        masm.addPtr(Imm32(1), current_position);
+
+        // Compare to end of match, and loop if not done.
+        masm.branchPtr(Assembler::Below, current_position, temp1, &loop);
+        masm.jump(&success);
+
+        masm.bind(&fail);
+
+        // Restore original values before failing.
+        masm.pop(current_position);
+        JumpOrBacktrack(on_no_match);
+
+        masm.bind(&success);
+
+        // Drop original character position value.
+        masm.addPtr(Imm32(sizeof(uintptr_t)), StackPointer);
+
+        // Compute new value of character position after the matched part.
+        masm.subPtr(input_end_pointer, current_position);
     } else {
         JS_ASSERT(mode_ == JSCHAR);
 

js/src/jit/arm/MacroAssembler-arm.cpp

@@ -1975,6 +1975,12 @@ MacroAssemblerARMCompat::or32(Imm32 imm, const Address &dest)
     store32(ScratchRegister, dest);
 }
 
+void
+MacroAssemblerARMCompat::or32(Imm32 imm, Register dest)
+{
+    ma_orr(imm, dest);
+}
+
 void
 MacroAssemblerARMCompat::xorPtr(Imm32 imm, Register dest)
 {

js/src/jit/arm/MacroAssembler-arm.h

@@ -1311,6 +1311,7 @@ class MacroAssemblerARMCompat : public MacroAssemblerARM
     void and32(Imm32 imm, Register dest);
     void and32(Imm32 imm, const Address &dest);
     void and32(const Address &src, Register dest);
+    void or32(Imm32 imm, Register dest);
     void or32(Imm32 imm, const Address &dest);
     void xorPtr(Imm32 imm, Register dest);
     void xorPtr(Register src, Register dest);