[WinEH] Update exception pointer registers

Summary:
The CLR's personality routine passes these in rdx/edx, not rax/eax.

Make getExceptionPointerRegister a virtual method parameterized by
personality function to allow making this distinction.

Similarly make getExceptionSelectorRegister a virtual method parameterized
by personality function, for symmetry.


Reviewers: pgavlin, majnemer, rnk

Subscribers: jyknight, dsanders, llvm-commits

Differential Revision: http://reviews.llvm.org/D14344

llvm-svn: 252383

2 files changed, 21 insertions, 10 deletions

diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
index f4919dd9acc..8a4dd5fab3d 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -827,15 +827,7 @@ PPCTargetLowering::PPCTargetLowering(const PPCTargetMachine &TM,
     setLibcallName(RTLIB::SRA_I128, nullptr);
   }
 
-  if (isPPC64) {
-    setStackPointerRegisterToSaveRestore(PPC::X1);
-    setExceptionPointerRegister(PPC::X3);
-    setExceptionSelectorRegister(PPC::X4);
-  } else {
-    setStackPointerRegisterToSaveRestore(PPC::R1);
-    setExceptionPointerRegister(PPC::R3);
-    setExceptionSelectorRegister(PPC::R4);
-  }
+  setStackPointerRegisterToSaveRestore(isPPC64 ? PPC::X1 : PPC::R1);
 
   // We have target-specific dag combine patterns for the following nodes:
   setTargetDAGCombine(ISD::SINT_TO_FP);
@@ -11532,6 +11524,16 @@ PPCTargetLowering::getScratchRegisters(CallingConv::ID) const {
   return ScratchRegs;
 }
 
+unsigned PPCTargetLowering::getExceptionPointerRegister(
+    const Constant *PersonalityFn) const {
+  return Subtarget.isPPC64() ? PPC::X3 : PPC::R3;
+}
+
+unsigned PPCTargetLowering::getExceptionSelectorRegister(
+    const Constant *PersonalityFn) const {
+  return Subtarget.isPPC64() ? PPC::X4 : PPC::R4;
+}
+
 bool
 PPCTargetLowering::shouldExpandBuildVectorWithShuffles(
                      EVT VT , unsigned DefinedValues) const {
diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.h b/llvm/lib/Target/PowerPC/PPCISelLowering.h
index cbd5add8488..415c47c286e 100644
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.h
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.h
@@ -655,8 +655,17 @@ namespace llvm {
       return Ty->isArrayTy();
     }
 
-  private:
+    /// If a physical register, this returns the register that receives the
+    /// exception address on entry to an EH pad.
+    unsigned
+    getExceptionPointerRegister(const Constant *PersonalityFn) const override;
 
+    /// If a physical register, this returns the register that receives the
+    /// exception typeid on entry to a landing pad.
+    unsigned
+    getExceptionSelectorRegister(const Constant *PersonalityFn) const override;
+
+  private:
     struct ReuseLoadInfo {
       SDValue Ptr;
       SDValue Chain;