llvm-mirror/test/CodeGen/X86/fast-isel-select-cmp.ll
Juergen Ributzka 87fbbdf13d [FastISel][X86] Only fold the cmp into the select when both instructions are in the same basic block.
If the cmp is in a different basic block, then it is possible that not all
operands of that compare have defined registers. This can happen when one of
the operands to the cmp is a load and the load gets folded into the cmp. In
this case FastISel will skip the load instruction and the vreg is never
defined.

llvm-svn: 211730
2014-06-25 20:06:12 +00:00

51 lines
1.1 KiB
LLVM

; RUN: llc < %s -O0 -mtriple=x86_64-apple-darwin10 | FileCheck %s
; Test if we do not fold the cmp into select if the instructions are in
; different basic blocks.
define i32 @select_cmp_cmov_i32(i32 %a, i32 %b) {
; CHECK-LABEL: select_cmp_cmov_i32
; CHECK-LABEL: continue
; CHECK-NOT: cmp
%1 = icmp ult i32 %a, %b
br i1 %1, label %continue, label %exit
continue:
%2 = select i1 %1, i32 %a, i32 %b
ret i32 %2
exit:
ret i32 -1
}
define float @select_fcmp_oeq_f32(float %a, float %b, float %c, float %d) {
; CHECK-LABEL: select_fcmp_oeq_f32
; CHECK-LABEL: continue
; CHECK-NOT: cmp
%1 = fcmp oeq float %a, %b
br i1 %1, label %continue, label %exit
continue:
%2 = select i1 %1, float %c, float %d
ret float %2
exit:
ret float -1.0
}
define float @select_fcmp_one_f32(float %a, float %b, float %c, float %d) {
; CHECK-LABEL: select_fcmp_one_f32
; CHECK-LABEL: continue
; CHECK-NOT: ucomi
%1 = fcmp one float %a, %b
br i1 %1, label %continue, label %exit
continue:
%2 = select i1 %1, float %c, float %d
ret float %2
exit:
ret float -1.0
}