maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

Adding testcase for PR18886. 

Differential Revision: http://reviews.llvm.org/D3837

llvm-svn: 209645
This commit is contained in:
Dinesh Dwivedi 2014-05-27 06:44:25 +00:00
parent 1c04babce3
commit c0e6703360
1 changed files with 27 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

27
llvm/test/Analysis/ScalarEvolution/max-trip-count.ll
View File

@ -125,6 +125,33 @@ bar.exit: ; preds = %for.cond.i, %for.bo
ret i32 0
}
; PR18886: Indvars miscompile due to an incorrect max backedge taken count from SCEV.
; CHECK-LABEL: @pr18886
; CHECK: Loop %for.body: <multiple exits> Unpredictable backedge-taken count.
; CHECK: Loop %for.body: max backedge-taken count is 3
@aa = global i64 0, align 8
define i32 @pr18886() {
entry:
store i64 -21, i64* @aa, align 8
br label %for.body
for.body:
%storemerge1 = phi i64 [ -21, %entry ], [ %add, %for.cond ]
%tobool = icmp eq i64 %storemerge1, 0
%add = add nsw i64 %storemerge1, 8
br i1 %tobool, label %return, label %for.cond
for.cond:
store i64 %add, i64* @aa, align 8
%cmp = icmp slt i64 %add, 9
br i1 %cmp, label %for.body, label %return
return:
%retval.0 = phi i32 [ 1, %for.body ], [ 0, %for.cond ]
ret i32 %retval.0
}
; Here we have a must-exit loop latch that is not computable and a
; may-exit early exit that can only have one non-exiting iteration
; before the check is forever skipped.