Subzero: Use a setcc sequence for better icmp lowering.
For an example like:
%a = icmp eq i32 %b, %c
The original icmp lowering sequence for i8/i16/i32 was something like:
cmpl b, c
movb 1, a
je label
movb 0, a
label:
The improved sequence is:
cmpl b, c
sete a
In O2 mode, this doesn't help when successive compare/branch instructions are fused, but it does help when the boolean result needs to be saved and later used.
BUG= none
R=jvoung@chromium.org
Review URL: https://codereview.chromium.org/1118353005
12 files changed
