<< CurLoop->getHeader()->getName() << "\n");
bool MadeChange = false;
+
+ // The following transforms hoist stores/memsets into the loop pre-header.
+ // Give up if the loop has instructions may throw.
+ LoopSafetyInfo SafetyInfo;
+ computeLoopSafetyInfo(&SafetyInfo, CurLoop);
+ if (SafetyInfo.MayThrow)
+ return MadeChange;
+
// Scan all the blocks in the loop that are not in subloops.
for (auto *BB : CurLoop->getBlocks()) {
// Ignore blocks in subloops.
--- /dev/null
+; RUN: opt -loop-idiom < %s -S | FileCheck %s
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+declare void @ff()
+
+define void @test(i8* noalias nocapture %base, i64 %size) #1 {
+entry:
+ %cmp3 = icmp eq i64 %size, 0
+ br i1 %cmp3, label %for.end, label %for.body.preheader
+
+for.body.preheader: ; preds = %entry
+ br label %for.body
+
+for.body: ; preds = %for.body.preheader, %for.body
+; CHECK-LABEL: @test(
+; CHECK-NOT: llvm.memset
+ %indvars.iv = phi i64 [ 0, %for.body.preheader ], [ %indvars.iv.next, %for.body ]
+ tail call void @ff()
+ %arrayidx = getelementptr inbounds i8, i8* %base, i64 %indvars.iv
+ store i8 0, i8* %arrayidx, align 1
+ %indvars.iv.next = add i64 %indvars.iv, 1
+ %exitcond = icmp ne i64 %indvars.iv.next, %size
+ br i1 %exitcond, label %for.body, label %for.end.loopexit
+
+for.end.loopexit: ; preds = %for.body
+ br label %for.end
+
+for.end: ; preds = %for.end.loopexit, %entry
+ ret void
+}
+
+attributes #1 = { uwtable }