[PATCH] D118428: [clang-cl] Support the /JMC flag

[Hans Wennborg via Phabricator via cfe-commits]

hans added inline comments.


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Comment at: llvm/lib/CodeGen/TargetPassConfig.cpp:1096
+  if (TM->Options.JMCInstrument)
+    addPass(createJMCInstrumenterPass());
   addCodeGenPrepare();
----------------
ychen wrote:
> hans wrote:
> > could this be moved into addIRPasses()?
> Yes, it could. `CFGuardCheckPass` is there for targets with COFF. I didn't put it there because I plan to make it work with ELF in the next step, putting it here is convenient. I don't feel strongly though.
I think it would be better to move it to addIRPasses().


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Comment at: llvm/test/CodeGen/X86/jmc-instrument.ll:2
+; Check that the flag symbol is not full-qualified.
+; RUN: llc < %s -enable-jmc-instrument | FileCheck %s
+
----------------
ychen wrote:
> hans wrote:
> > hans wrote:
> > > Since it's an IR pass, I think we don't need to have an llc test at all.
> > I still think it's unusual to have an llc test for an IR pass. Are there any other examples where we do something similar?
> yes, it is pretty rare. I wanted to test the `CodeViewDebug.cpp` change, however, the code path only triggers when the JMC pass is run. Using `llc` came to mind. I'm open to any alternative.
Oh, I see. But does the test check the right thing, then? I only see CHECKs for instructions, not debug info.

And isn't it enough to use IR with a global variable in the .msvcjmc section as input? I think the tighter the test, the better.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D118428/new/

https://reviews.llvm.org/D118428