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| author | Erik Pilkington <erik.pilkington@gmail.com> | 2019-04-10 23:42:11 +0000 |
|---|---|---|
| committer | Erik Pilkington <erik.pilkington@gmail.com> | 2019-04-10 23:42:11 +0000 |
| commit | cb5c7bd9ebfa004751a1b8815a281f51de2083dc (patch) | |
| tree | afab549d77bf0b2dac02196a236c12667eea244d /llvm/test/Transforms/InstCombine/builtin-dynamic-object-size.ll | |
| parent | 2f46de8c0b253e40ea84bb99e6a77079abd86daa (diff) | |
| download | bcm5719-llvm-cb5c7bd9ebfa004751a1b8815a281f51de2083dc.tar.gz bcm5719-llvm-cb5c7bd9ebfa004751a1b8815a281f51de2083dc.zip | |
Fix a hang when lowering __builtin_dynamic_object_size
If the ObjectSizeOffsetEvaluator fails to fold the object size call, then it may
litter some unused instructions in the function. When done repeatably in
InstCombine, this results in an infinite loop. Fix this by tracking the set of
instructions that were inserted, then removing them on failure.
rdar://49172227
Differential revision: https://reviews.llvm.org/D60298
llvm-svn: 358146
Diffstat (limited to 'llvm/test/Transforms/InstCombine/builtin-dynamic-object-size.ll')
| -rw-r--r-- | llvm/test/Transforms/InstCombine/builtin-dynamic-object-size.ll | 34 |
1 files changed, 34 insertions, 0 deletions
diff --git a/llvm/test/Transforms/InstCombine/builtin-dynamic-object-size.ll b/llvm/test/Transforms/InstCombine/builtin-dynamic-object-size.ll index a0c2d139916..eabe3a4c4b7 100644 --- a/llvm/test/Transforms/InstCombine/builtin-dynamic-object-size.ll +++ b/llvm/test/Transforms/InstCombine/builtin-dynamic-object-size.ll @@ -71,6 +71,40 @@ entry: ; CHECK: ret i64 0 +@d = common global i8 0, align 1 +@c = common global i32 0, align 4 + +; Function Attrs: nounwind +define void @f() { +entry: + %.pr = load i32, i32* @c, align 4 + %tobool4 = icmp eq i32 %.pr, 0 + br i1 %tobool4, label %for.end, label %for.body + +for.body: ; preds = %entry, %for.body + %dp.05 = phi i8* [ %add.ptr, %for.body ], [ @d, %entry ] + %0 = tail call i64 @llvm.objectsize.i64.p0i8(i8* %dp.05, i1 false, i1 true, i1 true) + %conv = trunc i64 %0 to i32 + tail call void @bury(i32 %conv) #3 + %1 = load i32, i32* @c, align 4 + %idx.ext = sext i32 %1 to i64 + %add.ptr.offs = add i64 %idx.ext, 0 + %2 = add i64 undef, %add.ptr.offs + %add.ptr = getelementptr inbounds i8, i8* %dp.05, i64 %idx.ext + %add = shl nsw i32 %1, 1 + store i32 %add, i32* @c, align 4 + %tobool = icmp eq i32 %1, 0 + br i1 %tobool, label %for.end, label %for.body + +for.end: ; preds = %for.body, %entry + ret void +} + +; CHECK: define void @f() +; CHECK: call i64 @llvm.objectsize.i64.p0i8( + +declare void @bury(i32) local_unnamed_addr #2 + ; Function Attrs: nounwind allocsize(0) declare i8* @malloc(i64) |
