Allow kernels to be referenced in @llvm.global.annotations

---------------------------

GenXIntrinsics/lib/GenXIntrinsics/GenXSPIRVReaderAdaptor.cpp

@@ -486,8 +486,24 @@ static void rewriteKernelArguments(Function &F) {
     // All arguments are in old style.
     return;
 
-  // No uses. Fast composite is not converted in writer part for now.
-  assert(F.use_empty() && "FC is not supported yet");
+  // At the moment there are only two cases when kernel function with converted
+  // parameters can have users:
+  // 1. Kernel is called from another function via fast composite
+  //    For such kernels we just don't rewrite arguments on SPIRV write, so
+  //    there should not be presented on read
+  // 2. Kernel is referenced in @llvm.global.annotations
+  //    We have to replace the original function with the new one
+  if (!F.use_empty()) {
+    assert(F.hasOneUse());
+    auto *Bitcast = F.user_back();
+    assert(Bitcast->hasOneUse());
+    auto *Struct = Bitcast->user_back();
+    assert(Struct->hasOneUse());
+    auto *Array = Struct->user_back();
+    assert(Array->hasOneUse());
+    auto *GV = dyn_cast<GlobalVariable>(Array->user_back());
+    assert(GV && GV->getName() == "llvm.global.annotations");
+  }
 
   Function *NewF = transformKernelSignature(F, ArgDescs);
   F.getParent()->getFunctionList().insert(F.getIterator(), NewF);
@@ -521,6 +537,8 @@ static void rewriteKernelArguments(Function &F) {
     }
   }
 
+  F.mutateType(NewF->getType());
+  F.replaceAllUsesWith(NewF);
   F.eraseFromParent();
 }
 

GenXIntrinsics/test/Adaptors/annotated_args_reader.ll

@@ -19,6 +19,11 @@
 %opencl.image3d_rw_t = type opaque
 %opencl.sampler_t = type opaque
 
+@0 = private unnamed_addr constant [15 x i8] c"some attribute\00", section "llvm.metadata"
+@llvm.global.annotations = appending global [1 x { i8*, i8*, i8*, i32 }] [{ i8*, i8*, i8*, i32 } { i8* bitcast (void (%intel.buffer_rw_t addrspace(1)*, %opencl.image1d_rw_t addrspace(1)*, %opencl.image1d_buffer_rw_t addrspace(1)*, %opencl.image2d_rw_t addrspace(1)*, %opencl.image3d_rw_t addrspace(1)*, %opencl.sampler_t addrspace(2)*, i8 addrspace(1)*, <4 x i32>)* @test to i8*), i8* getelementptr inbounds ([15 x i8], [15 x i8]* @0, i32 0, i32 0), i8* undef, i32 undef }], section "llvm.metadata"
+; CHECK-LABEL: @llvm.global.annotations
+; CHECK void (i32, i32, i32, i32, i32, i32, i64, <4 x i32>)* @test
+
 define spir_kernel void @test(%intel.buffer_rw_t addrspace(1)* %buf, %opencl.image1d_rw_t addrspace(1)* %im1d, %opencl.image1d_buffer_rw_t addrspace(1)* %im1db, %opencl.image2d_rw_t addrspace(1)* %im2d, %opencl.image3d_rw_t addrspace(1)* %im3d, %opencl.sampler_t addrspace(2)* %samp, i8 addrspace(1)* %ptr, <4 x i32> %gen) #0 {
 ; CHECK-LABEL: @test(