[PATCH] D28307: Add Instruction number to LSR cost model (PR23384) part 1 of 3

[Quentin Colombet via Phabricator via llvm-commits]

qcolombet added inline comments.


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Comment at: test/Transforms/LoopStrengthReduce/X86/lsr-insns-1.ll:1
+; RUN: llc < %s -O2 -march=x86-64 -lsr-insns-cost -asm-verbose=0 | FileCheck %s
+
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evstupac wrote:
> qcolombet wrote:
> > I would like to see opt -loop-reduce checks as well.
> It is harder to see profit in IR as we are getting even more instructions (assuming target will combine them to complicated address or remove test on 0).
> The will be harder to understand the test goal, but it is not a big deal to add such.
I'm not really interested by checking the profit, more by checking that this does what we want with the fewer possible interaction with something else.
Like you said, CodeGen could be fragile so it is best if we have better isolated testing, which is what opt is going to achieve.


Repository:
  rL LLVM

https://reviews.llvm.org/D28307