[llvm] 825b7f0 - InlineSpiller: Fix copy identification bugs in isCopyOfBundle

[Matt Arsenault via llvm-commits]

Author: Matt Arsenault
Date: 2023-07-17T20:05:56-04:00
New Revision: 825b7f0ca5f2211ec3c93139f98d1e24048c225c

URL: https://github.com/llvm/llvm-project/commit/825b7f0ca5f2211ec3c93139f98d1e24048c225c
DIFF: https://github.com/llvm/llvm-project/commit/825b7f0ca5f2211ec3c93139f98d1e24048c225c.diff

LOG: InlineSpiller: Fix copy identification bugs in isCopyOfBundle

Noticed by inspection of
b7836d856206ec39509d42529f958c920368166b. This was checking if the
first instruction was a copy, not the current MI. It should fully
respect the isCopyInstr result. Hopefully this fixes a reported
regression which we can extract a test from.

Added: 
    

Modified: 
    llvm/lib/CodeGen/InlineSpiller.cpp

Removed: 
    


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diff  --git a/llvm/lib/CodeGen/InlineSpiller.cpp b/llvm/lib/CodeGen/InlineSpiller.cpp
index e797e6953bccc2..c62f3db9d32156 100644
--- a/llvm/lib/CodeGen/InlineSpiller.cpp
+++ b/llvm/lib/CodeGen/InlineSpiller.cpp
@@ -289,11 +289,12 @@ static Register isCopyOfBundle(const MachineInstr &FirstMI, Register Reg,
   MachineBasicBlock::const_instr_iterator I = FirstMI.getIterator();
   while (I->isBundledWithSucc()) {
     const MachineInstr &MI = *I;
-    if (!TII.isCopyInstr(FirstMI))
+    auto CopyInst = TII.isCopyInstr(MI);
+    if (!CopyInst)
       return Register();
 
-    const MachineOperand &DstOp = MI.getOperand(0);
-    const MachineOperand &SrcOp = MI.getOperand(1);
+    const MachineOperand &DstOp = *CopyInst->Destination;
+    const MachineOperand &SrcOp = *CopyInst->Source;
     if (DstOp.getReg() == Reg) {
       if (!SnipReg)
         SnipReg = SrcOp.getReg();