Convert INSERT_SUBREG to COPY in TwoAddressInstructionPass.
INSERT_SUBREG will now only appear in SSA machine instructions.
Fix the handling of partial redefs in ProcessImplicitDefs. This is now relevant
since partial redef COPY instructions appear.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107726 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/TwoAddressInstructionPass.cpp b/lib/CodeGen/TwoAddressInstructionPass.cpp
index 4d4318d..efe14e6 100644
--- a/lib/CodeGen/TwoAddressInstructionPass.cpp
+++ b/lib/CodeGen/TwoAddressInstructionPass.cpp
@@ -1218,6 +1218,19 @@
DEBUG(dbgs() << "\t\trewrite to:\t" << *mi);
}
+ // Rewrite INSERT_SUBREG as COPY now that we no longer need SSA form.
+ if (mi->isInsertSubreg()) {
+ // From %reg = INSERT_SUBREG %reg, %subreg, subidx
+ // To %reg:subidx = COPY %subreg
+ unsigned SubIdx = mi->getOperand(3).getImm();
+ mi->RemoveOperand(3);
+ assert(mi->getOperand(0).getSubReg() == 0 && "Unexpected subreg idx");
+ mi->getOperand(0).setSubReg(SubIdx);
+ mi->RemoveOperand(1);
+ mi->setDesc(TII->get(TargetOpcode::COPY));
+ DEBUG(dbgs() << "\t\tconvert to:\t" << *mi);
+ }
+
// Clear TiedOperands here instead of at the top of the loop
// since most instructions do not have tied operands.
TiedOperands.clear();