[PATCH] D44958: [PostRASink]Add register dependency check for implicit operands

[Francis Visoiu Mistrih via Phabricator via llvm-commits]

thegameg added inline comments.


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Comment at: lib/CodeGen/MachineSink.cpp:1126
 
-    unsigned DefReg = MI->getOperand(0).getReg();
-    unsigned SrcReg = MI->getOperand(1).getReg();
+    SmallVector<std::pair<unsigned, unsigned>, 2> UsedRegsInCopy;
+    SmallVector<unsigned, 2> DefedRegsInCopy;
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junbuml wrote:
> thegameg wrote:
> > Any particular reason why we need to store both the register and the operand idx?
> The operand idx will be used in clearKillFlags() to set the kill flag in src reg of the Copy sunk if the src reg is killed in an instruction placed between Copy and the end of the block.
Right, I was just curious why not only use the operand idx and use MI.getOperand(OpIdx).getReg() to retrieve the register.


https://reviews.llvm.org/D44958