[PATCH] D52564: [PPC64] Add test for toc-restore on recursive call.

[Sean Fertile via Phabricator via llvm-commits]

sfertile added inline comments.


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Comment at: test/ELF/ppc64-toc-restore-recursive-call.s:41
+    addi 5, 3, -1
+    mulld 4, 4, 3
+    mr 3, 5
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MaskRay wrote:
> Are these extra operations (addi, mulld, ...) needed to make the test feel more authentic?
essentially. Its from one of the unit tests I wrote to figure out how we could have a recursive function call that crossed module boundaries, so I needed some 'testable' behavior.


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Comment at: test/ELF/ppc64-toc-restore-recursive-call.s:44
+    bl recursive_func
+    nop
+    mr 4, 3
----------------
MaskRay wrote:
> Is this related to the behavior of powerpc gcc >= 5.0?
> 
> https://sourceware.org/git/?p=binutils-gdb.git;a=blob;f=gold/powerpc.cc;hb=4e57b456393946cb4f90131b78e162cdec903c8a#l9069
> 
> 
> We had a discussion in https://reviews.llvm.org/D46204 that pre-5 versions of GCC did not emit a nop after bl.
Yes that discussion is what prompted this, this test is for documenting that we **need** the toc restore following the recursive call.


Repository:
  rLLD LLVM Linker

https://reviews.llvm.org/D52564