llvm-6502/test/CodeGen/ARM/machine-cse-cmp.ll
Manman Ren 39834da697 CSE: allow PerformTrivialCoalescing to check copies across basic block
boundaries.

Given the following case:
BB0
  %vreg1<def> = SUBrr %vreg0, %vreg7
  %vreg2<def> = COPY %vreg7
BB1
  %vreg10<def> = SUBrr %vreg0, %vreg2
We should be able to CSE between SUBrr in BB0 and SUBrr in BB1.

rdar://12462006


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168717 91177308-0d34-0410-b5e6-96231b3b80d8
2012-11-27 18:58:41 +00:00

80 lines
2.0 KiB
LLVM

; RUN: llc < %s -mtriple=armv7-apple-ios | FileCheck %s
;rdar://8003725
@G1 = external global i32
@G2 = external global i32
define i32 @f1(i32 %cond1, i32 %x1, i32 %x2, i32 %x3) {
entry:
; CHECK: f1:
; CHECK: cmp
; CHECK: moveq
; CHECK-NOT: cmp
; CHECK: mov{{eq|ne}}
%tmp1 = icmp eq i32 %cond1, 0
%tmp2 = select i1 %tmp1, i32 %x1, i32 %x2
%tmp3 = select i1 %tmp1, i32 %x2, i32 %x3
%tmp4 = add i32 %tmp2, %tmp3
ret i32 %tmp4
}
@foo = external global i32
@bar = external global [250 x i8], align 1
; CSE of cmp across BB boundary
; rdar://10660865
define void @f2() nounwind ssp {
entry:
; CHECK: f2:
; CHECK: cmp
; CHECK: poplt
; CHECK-NOT: cmp
; CHECK: movle
%0 = load i32* @foo, align 4
%cmp28 = icmp sgt i32 %0, 0
br i1 %cmp28, label %for.body.lr.ph, label %for.cond1.preheader
for.body.lr.ph: ; preds = %entry
%1 = icmp sgt i32 %0, 1
%smax = select i1 %1, i32 %0, i32 1
call void @llvm.memset.p0i8.i32(i8* getelementptr inbounds ([250 x i8]* @bar, i32 0, i32 0), i8 0, i32 %smax, i32 1, i1 false)
unreachable
for.cond1.preheader: ; preds = %entry
ret void
}
declare void @llvm.memset.p0i8.i32(i8* nocapture, i8, i32, i32, i1) nounwind
; rdar://12462006
define i8* @f3(i8* %base, i32* nocapture %offset, i32 %size) nounwind {
entry:
; CHECK: f3:
; CHECK-NOT: sub
; CHECK: cmp
; CHECK: blt
%0 = load i32* %offset, align 4
%cmp = icmp slt i32 %0, %size
%s = sub nsw i32 %0, %size
%size2 = sub nsw i32 %size, 0
br i1 %cmp, label %return, label %if.end
if.end:
; We are checking cse between %sub here and %s in entry block.
%sub = sub nsw i32 %0, %size2
%s2 = sub nsw i32 %s, %size
%s3 = sub nsw i32 %sub, %s2
; CHECK: sub [[R1:r[0-9]+]], [[R2:r[0-9]+]], r2
; CHECK: sub [[R3:r[0-9]+]], [[R1]], r2
; CHECK: sub [[R4:r[0-9]+]], [[R1]], [[R3]]
; CHECK-NOT: sub
; CHECK: str
store i32 %s3, i32* %offset, align 4
%add.ptr = getelementptr inbounds i8* %base, i32 %sub
br label %return
return:
%retval.0 = phi i8* [ %add.ptr, %if.end ], [ null, %entry ]
ret i8* %retval.0
}