[llvm] [SPIR-V] Add lowering of ptrtoaddr (PR #184577)

[Juan Manuel Martinez Caamaño via llvm-commits]

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@@ -1725,6 +1726,16 @@ Instruction *SPIRVEmitIntrinsics::visitBitCastInst(BitCastInst &I) {
   return NewI;
 }
 
+Instruction *SPIRVEmitIntrinsics::visitPtrToAddrInst(PtrToAddrInst &I) {
+  // Replace PtrToAddr with PtrToInt.
+  auto *PtrToInt =
+      CastInst::Create(Instruction::PtrToInt, I.getOperand(0), I.getType());
+  PtrToInt->insertBefore(I.getIterator());
+  replaceAllUsesWith(&I, PtrToInt);
+  I.eraseFromParent();
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jmmartinez wrote:

I'd add an assertion about the assumption we're making here (check the method `PointerSpec &DataLayout::getPointerSpec(uint32_t AddrSpace)`).

For example, AMDGPU has fat pointers with bounds checking and strides.

https://github.com/llvm/llvm-project/pull/184577