[llvm-commits] [PATCH] Replace SUB with CMP if possible on X86

[Manman Ren]

PING

On May 30, 2012, at 1:55 PM, Manman Ren wrote:

> 
> SUB with memory operand should not be optimized.
> Updated patch is attached.
> 
> Manman
> <convert_sub_to_cmp.patch>
> On May 30, 2012, at 11:44 AM, Manman Ren wrote:
> 
>> 
>> Hi All,
>> 
>> This patch is to optimize generated code from
>> 	movq	%rdi, %rax
>> 	subq	%rsi, %rax
>> 	cmovsq	%rsi, %rdi
>> 	movq	%rdi, %rax
>> 	
>> to
>> 	cmpq	%rsi, %rdi
>> 	cmovsq	%rsi, %rdi
>> 	movq	%rdi, %rax
>> 
>> The only criterion to perform this optimization is that the actual result of SUB is not used.
>> 
>> Thanks,
>> Manman
>> 
>> <convert_sub_to_cmp.patch>
>