llvm-capstone/polly/test/ScopDetectionDiagnostics/ReportUnreachableInExit.ll
Tobias Grosser 134a572951 [ScopDetection] Do not detect scops that exit to an unreachable
Scops that exit with an unreachable are today still permitted, but make little
sense to optimize. We therefore can already skip them during scop detection.
This speeds up scop detection in certain cases and also ensures that bugpoint
does not introduce unreachables when reducing test cases.

In practice this change should have little impact, as the performance of
unreachable code is unlikely to matter.

This commit is part of a series that makes Polly more robust in the presence
of unreachables.

llvm-svn: 297151
2017-03-07 15:50:43 +00:00

32 lines
827 B
LLVM

; RUN: opt %loadPolly -polly-detect -analyze < %s \
; RUN: -pass-remarks-missed="polly-detect" 2>&1 | FileCheck %s
; void f(long A[], long N) {
; long i;
; for (i = 0; i < N; ++i)
; A[i] = i;
; unreachable()
; }
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128"
define void @f(i64* %A, i64 %N) nounwind {
entry:
fence seq_cst
br label %for.i
for.i:
%indvar = phi i64 [ 0, %entry ], [ %indvar.next, %for.i ]
%scevgep = getelementptr i64, i64* %A, i64 %indvar
store i64 %indvar, i64* %scevgep
%indvar.next = add nsw i64 %indvar, 1
%exitcond = icmp eq i64 %indvar.next, %N
br i1 %exitcond, label %return, label %for.i
return:
fence seq_cst
unreachable
}
; CHECK: Unreachable in exit block