llvm-6502/test/Transforms/InstCombine/canonicalize_branch.ll
Chandler Carruth 602650c988 Add a routine to swap branch instruction operands, and update any
profile metadata at the same time. Use it to preserve metadata attached
to a branch when re-writing it in InstCombine.

Add metadata to the canonicalize_branch InstCombine test, and check that
it is tranformed correctly.

Reviewed by Nick Lewycky!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142168 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-17 01:11:57 +00:00

70 lines
1.6 KiB
LLVM

; RUN: opt < %s -instcombine -S | FileCheck %s
; Test an already canonical branch to make sure we don't flip those.
define i32 @test0(i32 %X, i32 %Y) {
%C = icmp eq i32 %X, %Y
br i1 %C, label %T, label %F, !prof !0
; CHECK: @test0
; CHECK: %C = icmp eq i32 %X, %Y
; CHECK: br i1 %C, label %T, label %F
T:
ret i32 12
F:
ret i32 123
}
define i32 @test1(i32 %X, i32 %Y) {
%C = icmp ne i32 %X, %Y
br i1 %C, label %T, label %F, !prof !1
; CHECK: @test1
; CHECK: %C = icmp eq i32 %X, %Y
; CHECK: br i1 %C, label %F, label %T
T:
ret i32 12
F:
ret i32 123
}
define i32 @test2(i32 %X, i32 %Y) {
%C = icmp ule i32 %X, %Y
br i1 %C, label %T, label %F, !prof !2
; CHECK: @test2
; CHECK: %C = icmp ugt i32 %X, %Y
; CHECK: br i1 %C, label %F, label %T
T:
ret i32 12
F:
ret i32 123
}
define i32 @test3(i32 %X, i32 %Y) {
%C = icmp uge i32 %X, %Y
br i1 %C, label %T, label %F, !prof !3
; CHECK: @test3
; CHECK: %C = icmp ult i32 %X, %Y
; CHECK: br i1 %C, label %F, label %T
T:
ret i32 12
F:
ret i32 123
}
!0 = metadata !{metadata !"branch_weights", i32 1, i32 2}
!1 = metadata !{metadata !"branch_weights", i32 3, i32 4}
!2 = metadata !{metadata !"branch_weights", i32 5, i32 6}
!3 = metadata !{metadata !"branch_weights", i32 7, i32 8}
; Base case shouldn't change.
; CHECK: !0 = {{.*}} i32 1, i32 2}
; Ensure that the branch metadata is reversed to match the reversals above.
; CHECK: !1 = {{.*}} i32 4, i32 3}
; CHECK: !2 = {{.*}} i32 6, i32 5}
; CHECK: !3 = {{.*}} i32 8, i32 7}