[PATCH] D122220: [InlineAsm] Add support for address operands ("p").

[Xiang Zhang via Phabricator via llvm-commits]

xiangzhangllvm added a comment.

In my eye, the reason we need the "p" is Front End miss handle the constrain "*", so the "m" and "*m" have the same action at qWvod14G9 <https://godbolt.org/z/qWvod14G9> 
(both isIndirect)

In IR level the constrain "p" is equal with "m" (TargetLowering::C_Memory +  !isIndirect)



================
Comment at: llvm/lib/CodeGen/CodeGenPrepare.cpp:4838
     // If this asm operand is our Value*, and if it isn't an indirect memory
-    // operand, we can't fold it!
+    // operand, we can't fold it!  TODO: Also handle C_Address?
     if (OpInfo.CallOperandVal == OpVal &&
----------------
I think C_Address the should return false. It is direct mem (!OpInfo.isIndirect). So no need change here.


================
Comment at: llvm/lib/CodeGen/CodeGenPrepare.cpp:5621
 
+    // TODO: Also handle C_Address?
     if (OpInfo.ConstraintType == TargetLowering::C_Memory &&
----------------
I think we can handle the C_Address.
As the comment ahead optimizeMemoryInst, this is used to
"Sink addressing mode computation immediate before MemoryInst if doing so
 can be done without increasing register pressure."
Anyway that is not a big problem.


CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D122220/new/

https://reviews.llvm.org/D122220