mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-10-21 20:12:56 +02:00
ad2555c9a3
exact backedge taken count, when checking for infinite loops. This allows it to delete loops with multiple exit conditions. llvm-svn: 84952
28 lines
617 B
LLVM
28 lines
617 B
LLVM
; RUN: opt < %s -loop-deletion -S | FileCheck %s
|
|
|
|
; ScalarEvolution can prove the loop iteration is finite, even though
|
|
; it can't represent the exact trip count as an expression. That's
|
|
; good enough to let the loop be deleted.
|
|
|
|
; CHECK: entry:
|
|
; CHECK-NEXT: br label %return
|
|
|
|
; CHECK: return:
|
|
; CHECK-NEXT: ret void
|
|
|
|
define void @foo(i64 %n, i64 %m) nounwind {
|
|
entry:
|
|
br label %bb
|
|
|
|
bb:
|
|
%x.0 = phi i64 [ 0, %entry ], [ %t0, %bb ]
|
|
%t0 = add i64 %x.0, 1
|
|
%t1 = icmp slt i64 %x.0, %n
|
|
%t3 = icmp sgt i64 %x.0, %m
|
|
%t4 = and i1 %t1, %t3
|
|
br i1 %t4, label %bb, label %return
|
|
|
|
return:
|
|
ret void
|
|
}
|