Revert 93158. It's breaking quite a few x86_64 tests.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93185 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelDAGToDAG.cpp b/lib/Target/X86/X86ISelDAGToDAG.cpp
index e2a53d1..c795b62 100644
--- a/lib/Target/X86/X86ISelDAGToDAG.cpp
+++ b/lib/Target/X86/X86ISelDAGToDAG.cpp
@@ -1873,6 +1873,7 @@
unsigned LoReg, HiReg, ClrReg;
unsigned ClrOpcode, SExtOpcode;
+ EVT ClrVT = NVT;
switch (NVT.getSimpleVT().SimpleTy) {
default: llvm_unreachable("Unsupported VT!");
case MVT::i8:
@@ -1882,7 +1883,7 @@
break;
case MVT::i16:
LoReg = X86::AX; HiReg = X86::DX;
- ClrOpcode = X86::MOV16r0; ClrReg = X86::DX;
+ ClrOpcode = X86::MOV32r0; ClrReg = X86::EDX; ClrVT = MVT::i32;
SExtOpcode = X86::CWD;
break;
case MVT::i32:
@@ -1892,7 +1893,7 @@
break;
case MVT::i64:
LoReg = X86::RAX; ClrReg = HiReg = X86::RDX;
- ClrOpcode = X86::MOV64r0;
+ ClrOpcode = ~0U; // NOT USED.
SExtOpcode = X86::CQO;
break;
}
@@ -1931,8 +1932,24 @@
SDValue(CurDAG->getMachineNode(SExtOpcode, dl, MVT::Flag, InFlag),0);
} else {
// Zero out the high part, effectively zero extending the input.
- SDValue ClrNode =
- SDValue(CurDAG->getMachineNode(ClrOpcode, dl, NVT), 0);
+ SDValue ClrNode;
+
+ if (NVT.getSimpleVT() == MVT::i64) {
+ ClrNode = SDValue(CurDAG->getMachineNode(X86::MOV32r0, dl, MVT::i32),
+ 0);
+ // We just did a 32-bit clear, insert it into a 64-bit register to
+ // clear the whole 64-bit reg.
+ SDValue Zero = CurDAG->getTargetConstant(0, MVT::i64);
+ SDValue SubRegNo =
+ CurDAG->getTargetConstant(X86::SUBREG_32BIT, MVT::i32);
+ ClrNode =
+ SDValue(CurDAG->getMachineNode(TargetInstrInfo::SUBREG_TO_REG, dl,
+ MVT::i64, Zero, ClrNode, SubRegNo),
+ 0);
+ } else {
+ ClrNode = SDValue(CurDAG->getMachineNode(ClrOpcode, dl, ClrVT), 0);
+ }
+
InFlag = CurDAG->getCopyToReg(CurDAG->getEntryNode(), dl, ClrReg,
ClrNode, InFlag).getValue(1);
}