llvm-6502/test/Transforms/LoopDeletion/simplify-then-delete.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

66 lines
1.2 KiB
LLVM

; RUN: opt < %s -S -indvars -loop-deletion -simplifycfg | FileCheck %s
; PR5794
; Indvars and loop deletion should be able to eliminate all looping
; in this testcase.
; CHECK: define i32 @pmat(i32 %m, i32 %n, double* %y) nounwind {
; CHECK-NEXT: entry:
; CHECK-NEXT: ret i32 0
; CHECK-NEXT: }
target datalayout = "e-p:64:64:64"
define i32 @pmat(i32 %m, i32 %n, double* %y) nounwind {
entry:
%cmp4 = icmp sgt i32 %m, 0
br i1 %cmp4, label %bb.n10, label %w.e12
w.c:
%cmp = icmp slt i32 %inc11, %m
br i1 %cmp, label %w.c2.p, label %w.c.w.e12c
w.c.w.e12c:
br label %w.c.w.e12c.s
w.c.w.e12c.s:
br label %w.e12
bb.n10:
%cmp51 = icmp sgt i32 %n, 0
br i1 %cmp51, label %bb.n10.w.c.w.e12c.sc, label %bb.n10.bb.n10.sc
bb.n10.bb.n10.sc:
br label %bb.n10.s
bb.n10.w.c.w.e12c.sc:
br label %w.c.w.e12c.s
bb.n10.s:
br label %w.c2.p
w.c2.p:
%i.05 = phi i32 [ 0, %bb.n10.s ], [ %inc11, %w.c ]
br i1 false, label %bb.n, label %w.e
w.c2:
br i1 undef, label %w.b6, label %w.c2.w.ec
w.c2.w.ec:
br label %w.e
bb.n:
br label %w.b6
w.b6:
br label %w.c2
w.e:
%i.08 = phi i32 [ undef, %w.c2.w.ec ], [ %i.05, %w.c2.p ]
%inc11 = add nsw i32 %i.08, 1
br label %w.c
w.e12:
ret i32 0
}