[AMDGPU] Get address space mapping by target triple environment

As we introduced target triple environment amdgiz and amdgizcl, the address
space values are no longer enums. We have to decide the value by target triple.

The basic idea is to use struct AMDGPUAS to represent address space values.
For address space values which are not depend on target triple, use static
const members, so that they don't occupy extra memory space and is equivalent
to a compile time constant.

Since the struct is lightweight and cheap, it can be created on the fly at
the point of usage. Or it can be added as member to a pass and created at
the beginning of the run* function.

Differential Revision: https://reviews.llvm.org/D31284

llvm-svn: 298846

1 files changed, 6 insertions, 8 deletions

diff --git a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
index b57cc00a71f..af3c9ff28df 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUISelLowering.cpp
@@ -59,6 +59,7 @@ EVT AMDGPUTargetLowering::getEquivalentMemType(LLVMContext &Ctx, EVT VT) {
 AMDGPUTargetLowering::AMDGPUTargetLowering(const TargetMachine &TM,
                                            const AMDGPUSubtarget &STI)
     : TargetLowering(TM), Subtarget(&STI) {
+  AMDGPUASI = AMDGPU::getAMDGPUAS(TM);
   // Lower floating point store/load to integer store/load to reduce the number
   // of patterns in tablegen.
   setOperationAction(ISD::LOAD, MVT::f32, Promote);
@@ -967,19 +968,16 @@ SDValue AMDGPUTargetLowering::LowerGlobalAddress(AMDGPUMachineFunction* MFI,
   GlobalAddressSDNode *G = cast<GlobalAddressSDNode>(Op);
   const GlobalValue *GV = G->getGlobal();
 
-  switch (G->getAddressSpace()) {
-  case AMDGPUAS::LOCAL_ADDRESS: {
+  if  (G->getAddressSpace() == AMDGPUASI.LOCAL_ADDRESS) {
     // XXX: What does the value of G->getOffset() mean?
     assert(G->getOffset() == 0 &&
          "Do not know what to do with an non-zero offset");
 
     // TODO: We could emit code to handle the initialization somewhere.
-    if (hasDefinedInitializer(GV))
-      break;
-
-    unsigned Offset = MFI->allocateLDSGlobal(DL, *GV);
-    return DAG.getConstant(Offset, SDLoc(Op), Op.getValueType());
-  }
+    if (!hasDefinedInitializer(GV)) {
+      unsigned Offset = MFI->allocateLDSGlobal(DL, *GV);
+      return DAG.getConstant(Offset, SDLoc(Op), Op.getValueType());
+    }
   }
 
   const Function &Fn = *DAG.getMachineFunction().getFunction();