llvm/test/CodeGen/X86/cmov-into-branch.ll
Benjamin Kramer 77c4ef8a47 Switch the select to branch transformation on by default.
The primitive conservative heuristic seems to give a slight overall
improvement while not regressing stuff. Make it available to wider
testing. If you notice any speed regressions (or significant code
size regressions) let me know!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@156258 91177308-0d34-0410-b5e6-96231b3b80d8
2012-05-06 14:25:16 +00:00

64 lines
1.5 KiB
LLVM

; RUN: llc -march=x86-64 -mcpu=core2 < %s | FileCheck %s
; cmp with single-use load, should not form cmov.
define i32 @test1(double %a, double* nocapture %b, i32 %x, i32 %y) {
%load = load double* %b, align 8
%cmp = fcmp olt double %load, %a
%cond = select i1 %cmp, i32 %x, i32 %y
ret i32 %cond
; CHECK: test1:
; CHECK: ucomisd
; CHECK-NOT: cmov
; CHECK: j
; CHECK-NOT: cmov
}
; Sanity check: no load.
define i32 @test2(double %a, double %b, i32 %x, i32 %y) {
%cmp = fcmp ogt double %a, %b
%cond = select i1 %cmp, i32 %x, i32 %y
ret i32 %cond
; CHECK: test2:
; CHECK: ucomisd
; CHECK: cmov
}
; Multiple uses of %a, should not form cmov.
define i32 @test3(i32 %a, i32* nocapture %b, i32 %x) {
%load = load i32* %b, align 4
%cmp = icmp ult i32 %load, %a
%cond = select i1 %cmp, i32 %a, i32 %x
ret i32 %cond
; CHECK: test3:
; CHECK: cmpl
; CHECK-NOT: cmov
; CHECK: j
; CHECK-NOT: cmov
}
; Multiple uses of the load.
define i32 @test4(i32 %a, i32* nocapture %b, i32 %x, i32 %y) {
%load = load i32* %b, align 4
%cmp = icmp ult i32 %load, %a
%cond = select i1 %cmp, i32 %x, i32 %y
%add = add i32 %cond, %load
ret i32 %add
; CHECK: test4:
; CHECK: cmpl
; CHECK: cmov
}
; Multiple uses of the cmp.
define i32 @test5(i32 %a, i32* nocapture %b, i32 %x, i32 %y) {
%load = load i32* %b, align 4
%cmp = icmp ult i32 %load, %a
%cmp1 = icmp ugt i32 %load, %a
%cond = select i1 %cmp1, i32 %a, i32 %y
%cond5 = select i1 %cmp, i32 %cond, i32 %x
ret i32 %cond5
; CHECK: test5:
; CHECK: cmpl
; CHECK: cmov
; CHECK: cmov
}