llvm-6502/test/Transforms/IndVarSimplify/2003-09-12-MultiplePred.ll
Dan Gohman 8566963713 Make LoopSimplify change conditional branches in loop exiting blocks
which branch on undef to branch on a boolean constant for the edge
exiting the loop. This helps ScalarEvolution compute trip counts for
loops.

Teach ScalarEvolution to recognize single-value PHIs, when safe, and
ForgetSymbolicName to forget such single-value PHI nodes as apprpriate
in ForgetSymbolicName.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97126 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-25 06:57:05 +00:00

16 lines
437 B
LLVM

; RUN: opt < %s -indvars -S | grep indvar
define i32 @test() {
; <label>:0
br i1 true, label %LoopHead, label %LoopHead
LoopHead: ; preds = %LoopHead, %0, %0
%A = phi i32 [ 7, %0 ], [ 7, %0 ], [ %B, %LoopHead ] ; <i32> [#uses=1]
%B = add i32 %A, 1 ; <i32> [#uses=2]
br i1 true, label %LoopHead, label %Out
Out: ; preds = %LoopHead
ret i32 %B
}