SPIRVReader: Add OpSizeOf support (#2853)

The `OpSizeOf` instruction was added in SPIR-V 1.1, but not supported
yet.

Original commit:
KhronosGroup/SPIRV-LLVM-Translator@9aeb7eb92d7c0cb

Author: svenvh

llvm-spirv/lib/SPIRV/SPIRVReader.cpp

@@ -1567,6 +1567,15 @@ Value *SPIRVToLLVM::transValueWithoutDecoration(SPIRVValue *BV, Function *F,
   case OpUndef:
     return mapValue(BV, UndefValue::get(transType(BV->getType())));
 
+  case OpSizeOf: {
+    Type *ResTy = transType(BV->getType());
+    auto *BI = static_cast<SPIRVSizeOf *>(BV);
+    SPIRVType *TypeArg = reinterpret_cast<SPIRVType *>(BI->getOpValue(0));
+    Type *EltTy = transType(TypeArg->getPointerElementType());
+    uint64_t Size = M->getDataLayout().getTypeStoreSize(EltTy).getFixedValue();
+    return mapValue(BV, ConstantInt::get(ResTy, Size));
+  }
+
   case OpVariable:
   case OpUntypedVariableKHR: {
     auto *BVar = static_cast<SPIRVVariableBase *>(BV);

llvm-spirv/lib/SPIRV/libSPIRV/SPIRVEntry.h

@@ -1089,7 +1089,6 @@ _SPIRV_OP(NamedBarrierInitialize)
 _SPIRV_OP(MemoryNamedBarrier)
 _SPIRV_OP(GetKernelMaxNumSubgroups)
 _SPIRV_OP(GetKernelLocalSizeForSubgroupCount)
-_SPIRV_OP(SizeOf)
 #undef _SPIRV_OP
 
 } // namespace SPIRV

llvm-spirv/lib/SPIRV/libSPIRV/SPIRVInstruction.h

@@ -1622,6 +1622,16 @@ class SPIRVTranspose : public SPIRVInstruction {
   SPIRVId Matrix;
 };
 
+class SPIRVSizeOfInstBase : public SPIRVInstTemplateBase {
+protected:
+  VersionNumber getRequiredSPIRVVersion() const override {
+    return VersionNumber::SPIRV_1_1;
+  }
+};
+
+typedef SPIRVInstTemplate<SPIRVSizeOfInstBase, OpSizeOf, true, 4, false>
+    SPIRVSizeOf;
+
 class SPIRVUnary : public SPIRVInstTemplateBase {
 protected:
   void validate() const override {

llvm-spirv/lib/SPIRV/libSPIRV/SPIRVOpCodeEnum.h

@@ -291,6 +291,7 @@ _SPIRV_OP(ImageSparseTexelsResident, 316)
 _SPIRV_OP(NoLine, 317)
 _SPIRV_OP(AtomicFlagTestAndSet, 318)
 _SPIRV_OP(AtomicFlagClear, 319)
+_SPIRV_OP(SizeOf, 321)
 _SPIRV_OP(TypePipeStorage, 322)
 _SPIRV_OP(ConstantPipeStorage, 323)
 _SPIRV_OP(CreatePipeFromPipeStorage, 324)

llvm-spirv/test/OpSizeOf.spvasm

@@ -0,0 +1,33 @@
+; REQUIRES: spirv-as
+; RUN: spirv-as --target-env spv1.1 -o %t.spv %s
+; TODO: reenable spirv-val when OpSizeOf is supported.
+; R/U/N: spirv-val %t.spv
+; RUN: llvm-spirv -r -o - %t.spv | llvm-dis | FileCheck %s
+               OpCapability Addresses
+               OpCapability Kernel
+               OpMemoryModel Physical64 OpenCL
+               OpEntryPoint Kernel %f "testSizeOf"
+               OpName %p "p"
+       %void = OpTypeVoid
+       %bool = OpTypeBool
+        %i32 = OpTypeInt 32 0
+     %struct = OpTypeStruct %i32 %i32
+%_ptr_CrossWorkgroup_bool = OpTypePointer CrossWorkgroup %bool
+%_ptr_CrossWorkgroup_i32 = OpTypePointer CrossWorkgroup %i32
+%_ptr_CrossWorkgroup_struct = OpTypePointer CrossWorkgroup %struct
+       %fnTy = OpTypeFunction %void %_ptr_CrossWorkgroup_i32
+
+          %f = OpFunction %void None %fnTy
+          %p = OpFunctionParameter %_ptr_CrossWorkgroup_i32
+         %10 = OpLabel
+
+; CHECK: store i32 1, ptr addrspace(1) %p
+         %11 = OpSizeOf %i32 %_ptr_CrossWorkgroup_bool
+               OpStore %p %11
+
+; CHECK: store i32 8, ptr addrspace(1) %p
+         %12 = OpSizeOf %i32 %_ptr_CrossWorkgroup_struct
+               OpStore %p %12
+
+               OpReturn
+               OpFunctionEnd