[PATCH] D57054: [MachineOutliner][ARM][RFC] Add Machine Outliner support for ARM

Mon Jan 28 09:21:19 PST 2019

dmgreen added a comment.

The only increase I was seeing was because of D57254 <https://reviews.llvm.org/D57254> (and perhaps the alignment thing you mention, but that was very small/rare, iirc). The main part was definitely the exception handlers pulling in a big chunk more code. The other results were looking great.

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Comment at: lib/Target/ARM/ARMBaseInstrInfo.cpp:5431
+  unsigned AddrMode = (MI->getDesc().TSFlags & ARMII::AddrModeMask);
+  int Idx = MI->findRegisterUseOperandIdx(ARM::SP) + 1;
+  int64_t Offset = 0;
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yroux wrote:
> dmgreen wrote:
> > What if we are actually storing sp? As in something like,
> > t2STRi8 $sp, $r7, 12, ...
> hmm, there might be an issue if the stored value (with a fix-up) is used after the outlined code indeed, I think that this kind of issue didn't occurred in my tests because of the constraints made at lines 5645-5697, I'll try to exhibit the issue with an mir test. 
I think it was also trying to access operand Idx (= 1) as an Imm, not a Reg, which is what made me spot it. I can probably get a reproducer, if it would be useful.

Repository:
  rL LLVM

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D57054/new/

https://reviews.llvm.org/D57054