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arsenm · arsenm · commit af32e22adf57 · 2025-02-21T18:14:12.000+07:00
diff --git a/llvm/lib/CodeGen/RegAllocFast.cpp b/llvm/lib/CodeGen/RegAllocFast.cpp
@@ -1223,6 +1223,8 @@ bool RegAllocFastImpl::setPhysReg(MachineInstr &MI, MachineOperand &MO,
   assert(PhysReg && "assignments should always be to a valid physreg");
 
   if (LLVM_UNLIKELY(Assignment.Error)) {
+    // Make sure we don't set renamable in error scenarios, as we may have
+    // assigned to a reserved register.
     if (MO.isUse())
       MO.setIsUndef(true);
   }

Original file line number	Diff line number	Diff line change
`@@ -1223,6 +1223,8 @@ bool RegAllocFastImpl::setPhysReg(MachineInstr &MI, MachineOperand &MO,`
`1223`	`1223`	`assert(PhysReg && "assignments should always be to a valid physreg");`
`1224`	`1224`
`1225`	`1225`	`if (LLVM_UNLIKELY(Assignment.Error)) {`
	`1226`	`+ // Make sure we don't set renamable in error scenarios, as we may have`
	`1227`	`+ // assigned to a reserved register.`
`1226`	`1228`	`if (MO.isUse())`
`1227`	`1229`	`MO.setIsUndef(true);`
`1228`	`1230`	`}`