PPC64 passes arguments of integral type in i64 registers, not i32. Reflect this

by promoting smaller integral values (i32 at this point) to i64, then truncating
to get the wanted size.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48030 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 43 insertions, 26 deletions

diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index dffbf7cb27..7773fc9ee5 100644
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -1296,13 +1296,14 @@ static const unsigned *GetFPR(const PPCSubtarget &Subtarget) {
   return FPR;
 }
 
-SDOperand PPCTargetLowering::LowerFORMAL_ARGUMENTS(SDOperand Op, 
-                                       SelectionDAG &DAG,
-                                       int &VarArgsFrameIndex,
-                                       int &VarArgsStackOffset,
-                                       unsigned &VarArgsNumGPR,
-                                       unsigned &VarArgsNumFPR,
-                                       const PPCSubtarget &Subtarget) {
+SDOperand
+PPCTargetLowering::LowerFORMAL_ARGUMENTS(SDOperand Op, 
+                                         SelectionDAG &DAG,
+                                         int &VarArgsFrameIndex,
+                                         int &VarArgsStackOffset,
+                                         unsigned &VarArgsNumGPR,
+                                         unsigned &VarArgsNumFPR,
+                                         const PPCSubtarget &Subtarget) {
   // TODO: add description of PPC stack frame format, or at least some docs.
   //
   MachineFunction &MF = DAG.getMachineFunction();
@@ -1408,29 +1409,46 @@ SDOperand PPCTargetLowering::LowerFORMAL_ARGUMENTS(SDOperand Op,
     switch (ObjectVT) {
     default: assert(0 && "Unhandled argument type!");
     case MVT::i32:
-      // Double word align in ELF
-      if (Expand && isELF32_ABI) GPR_idx += (GPR_idx % 2);
-      if (GPR_idx != Num_GPR_Regs) {
-        unsigned VReg = RegInfo.createVirtualRegister(&PPC::GPRCRegClass);
-        RegInfo.addLiveIn(GPR[GPR_idx], VReg);
-        ArgVal = DAG.getCopyFromReg(Root, VReg, MVT::i32);
-        ++GPR_idx;
-      } else {
-        needsLoad = true;
-        ArgSize = PtrByteSize;
+      if (!isPPC64) {
+        // Double word align in ELF
+        if (Expand && isELF32_ABI) GPR_idx += (GPR_idx % 2);
+
+        if (GPR_idx != Num_GPR_Regs) {
+          unsigned VReg = RegInfo.createVirtualRegister(&PPC::GPRCRegClass);
+          RegInfo.addLiveIn(GPR[GPR_idx], VReg);
+          ArgVal = DAG.getCopyFromReg(Root, VReg, MVT::i32);
+          ++GPR_idx;
+        } else {
+          needsLoad = true;
+          ArgSize = PtrByteSize;
+        }
+        // Stack align in ELF
+        if (needsLoad && Expand && isELF32_ABI) 
+          ArgOffset += ((ArgOffset/4) % 2) * PtrByteSize;
+        // All int arguments reserve stack space in Macho ABI.
+        if (isMachoABI || needsLoad) ArgOffset += PtrByteSize;
+        break;
       }
-      // Stack align in ELF
-      if (needsLoad && Expand && isELF32_ABI) 
-        ArgOffset += ((ArgOffset/4) % 2) * PtrByteSize;
-      // All int arguments reserve stack space in Macho ABI.
-      if (isMachoABI || needsLoad) ArgOffset += PtrByteSize;
-      break;
-      
+      // FALLTHROUGH
     case MVT::i64:  // PPC64
       if (GPR_idx != Num_GPR_Regs) {
         unsigned VReg = RegInfo.createVirtualRegister(&PPC::G8RCRegClass);
         RegInfo.addLiveIn(GPR[GPR_idx], VReg);
         ArgVal = DAG.getCopyFromReg(Root, VReg, MVT::i64);
+
+        if (ObjectVT == MVT::i32) {
+          // PPC64 passes i8, i16, and i32 values in i64 registers. Promote
+          // value to MVT::i64 and then truncate to the correct register size.
+          if (Flags & ISD::ParamFlags::SExt)
+            ArgVal = DAG.getNode(ISD::AssertSext, MVT::i64, ArgVal,
+                                 DAG.getValueType(ObjectVT));
+          else if (Flags & ISD::ParamFlags::ZExt)
+            ArgVal = DAG.getNode(ISD::AssertZext, MVT::i64, ArgVal,
+                                 DAG.getValueType(ObjectVT));
+
+          ArgVal = DAG.getNode(ISD::TRUNCATE, MVT::i32, ArgVal);
+        }
+
         ++GPR_idx;
       } else {
         needsLoad = true;
@@ -1620,7 +1638,7 @@ static SDNode *isBLACompatibleAddress(SDOperand Op, SelectionDAG &DAG) {
 /// does not fit in registers.
 static SDOperand 
 CreateCopyOfByValArgument(SDOperand Src, SDOperand Dst, SDOperand Chain,
-                           unsigned Flags, SelectionDAG &DAG, unsigned Size) {
+                          unsigned Flags, SelectionDAG &DAG, unsigned Size) {
   unsigned Align = 1 <<
     ((Flags & ISD::ParamFlags::ByValAlign) >> ISD::ParamFlags::ByValAlignOffs);
   SDOperand AlignNode    = DAG.getConstant(Align, MVT::i32);
@@ -1742,7 +1760,6 @@ SDOperand PPCTargetLowering::LowerCALL(SDOperand Op, SelectionDAG &DAG,
     // On PPC64, promote integers to 64-bit values.
     if (isPPC64 && Arg.getValueType() == MVT::i32) {
       unsigned ExtOp = (Flags & 1) ? ISD::SIGN_EXTEND : ISD::ZERO_EXTEND;
-
       Arg = DAG.getNode(ExtOp, MVT::i64, Arg);
     }