YouCompleteMe/cpp/llvm/test/Transforms/LoopSimplify/2003-12-10-ExitBlocksProblem.ll
2012-07-05 17:51:06 -07:00

37 lines
1.1 KiB
LLVM

; LoopSimplify is breaking LICM on this testcase because the exit blocks from
; the loop are reachable from more than just the exit nodes: the exit blocks
; have predecessors from outside of the loop!
;
; This is distilled from a monsterous crafty example.
; RUN: opt < %s -licm -disable-output
@G = weak global i32 0 ; <i32*> [#uses=7]
define i32 @main() {
entry:
store i32 123, i32* @G
br label %loopentry.i
loopentry.i: ; preds = %endif.1.i, %entry
%tmp.0.i = load i32* @G ; <i32> [#uses=1]
%tmp.1.i = icmp eq i32 %tmp.0.i, 123 ; <i1> [#uses=1]
br i1 %tmp.1.i, label %Out.i, label %endif.0.i
endif.0.i: ; preds = %loopentry.i
%tmp.3.i = load i32* @G ; <i32> [#uses=1]
%tmp.4.i = icmp eq i32 %tmp.3.i, 126 ; <i1> [#uses=1]
br i1 %tmp.4.i, label %ExitBlock.i, label %endif.1.i
endif.1.i: ; preds = %endif.0.i
%tmp.6.i = load i32* @G ; <i32> [#uses=1]
%inc.i = add i32 %tmp.6.i, 1 ; <i32> [#uses=1]
store i32 %inc.i, i32* @G
br label %loopentry.i
Out.i: ; preds = %loopentry.i
store i32 0, i32* @G
br label %ExitBlock.i
ExitBlock.i: ; preds = %Out.i, %endif.0.i
%tmp.7.i = load i32* @G ; <i32> [#uses=1]
ret i32 %tmp.7.i
}