[PATCH] D15798: Fix for Bug 24852 (crash with -debug -instcombine)

[Xinliang David Li via llvm-commits]

On Wed, Jan 6, 2016 at 2:44 PM, Than McIntosh <thanm at google.com> wrote:
> thanm added a comment.
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>> This test case is quite large, can it be made smaller?
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> Most of the size is from the "-g" metadata, however the crash does not happen without metadata (in particular, compiling without "-g" makes the problem go away).  I could try to edit the metadata by hand -- are there any guidelines or suggestions you could offer with that regard?
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>> Also there are no changes to InstCombine, why are you running the pass?
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> The test is intended to make sure that you can run instcombine with "-debug" and not crash.
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> @joker.eph: I agree with your assessment.
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> ================
> Comment at: lib/IR/AsmWriter.cpp:3157
> @@ -3156,3 +3156,3 @@
>      Out << Separator;
> -    if (Kind < MDNames.size()) {
> +    if (TheModule && Kind < MDNames.size()) {
>        Out << "!";
> ----------------
> joker.eph wrote:
>> Why do you need `TheModule` here?
> TheModule is a null pointer in the case where the instruction has no parent BB.

This sounds like an invalid IR state ..

David

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> http://reviews.llvm.org/D15798
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