[PATCH] D57718: [PPC] Adjust the computed branch offset for the possible shorter distance

Wed Feb 13 15:31:49 PST 2019

Carrot added a comment.

In D57718#1396611 <https://reviews.llvm.org/D57718#1396611>, @sdardis wrote:

> In D57718#1393615 <https://reviews.llvm.org/D57718#1393615>, @Carrot wrote:
>
> > In D57718#1393504 <https://reviews.llvm.org/D57718#1393504>, @jsji wrote:
> >
> > > Any testcases that can show the problem and test the fix? Thanks.
> >
> >
> > It can only be triggered by a very large (>32KB) function body because the range of conditional branch is +/- 32KB.
> >
> > In our case, the large function body is caused by aggressive thinlto guided inlining.
> >
> > So no small test case can demonstrate the problem :(
>
>
> You can use the assembly directive '.space' to create arbitrary sized basic blocks. See test/CodeGen/RISCV/branch-relaxation.ll for examples.

Looks very useful. Will try it. Thanks a lot!

Repository:
  rL LLVM

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  https://reviews.llvm.org/D57718/new/

https://reviews.llvm.org/D57718