void StringCharFromCodeGenerator::GenerateFast(MacroAssembler* masm) {
// Fast case of Heap::LookupSingleCharacterStringFromCode.
-
- DCHECK(!a4.is(result_));
- DCHECK(!a4.is(code_));
-
- STATIC_ASSERT(kSmiTag == 0);
- DCHECK(base::bits::IsPowerOfTwo32(String::kMaxOneByteCharCodeU + 1));
- __ And(a4, code_, Operand(kSmiTagMask |
- ((~String::kMaxOneByteCharCodeU) << kSmiTagSize)));
- __ Branch(&slow_case_, ne, a4, Operand(zero_reg));
-
+ __ JumpIfNotSmi(code_, &slow_case_);
+ __ Branch(&slow_case_, hi, code_,
+ Operand(Smi::FromInt(String::kMaxOneByteCharCode)));
__ LoadRoot(result_, Heap::kSingleCharacterStringCacheRootIndex);
// At this point code register contains smi tagged one_byte char code.
- STATIC_ASSERT(kSmiTag == 0);
- __ SmiScale(a4, code_, kPointerSizeLog2);
- __ Daddu(result_, result_, a4);
+ __ SmiScale(at, code_, kPointerSizeLog2);
+ __ Daddu(result_, result_, at);
__ ld(result_, FieldMemOperand(result_, FixedArray::kHeaderSize));
- __ LoadRoot(a4, Heap::kUndefinedValueRootIndex);
- __ Branch(&slow_case_, eq, result_, Operand(a4));
+ __ LoadRoot(at, Heap::kUndefinedValueRootIndex);
+ __ Branch(&slow_case_, eq, result_, Operand(at));
__ bind(&exit_);
}
__ ld(a2, MemOperand(sp, kToOffset));
__ ld(a3, MemOperand(sp, kFromOffset));
-// Does not needed?
-// STATIC_ASSERT(kFromOffset == kToOffset + 4);
+
STATIC_ASSERT(kSmiTag == 0);
-// Does not needed?
-// STATIC_ASSERT(kSmiTagSize + kSmiShiftSize == 1);
// Utilize delay slots. SmiUntag doesn't emit a jump, everything else is
// safe in this case.
// a1: instance type
// a2: length
// a3: from index (untagged)
+ __ SmiTag(a3);
StringCharAtGenerator generator(v0, a3, a2, v0, &runtime, &runtime, &runtime,
STRING_INDEX_IS_NUMBER, RECEIVER_IS_STRING);
generator.GenerateFast(masm);