Do not create trampoline for fast composites

Fast composites are special kernel functions and do not require
trampolines.

Author: Anton Sidorenko

IGC/VectorCompiler/include/vc/Utils/GenX/KernelInfo.h

@@ -62,6 +62,11 @@ inline bool isKernel(const llvm::Function *F) {
 
 inline bool isKernel(const llvm::Function &F) { return isKernel(&F); }
 
+// Check if it is a fast composite.
+inline bool isCMCallable(const llvm::Function &F) {
+  return F.hasFnAttribute(llvm::genx::FunctionMD::CMCallable);
+}
+
 // Utility function to tell if a Function needs to be called using
 // vISA stack call ABI.
 inline bool requiresStackCall(const llvm::Function *F) {

IGC/VectorCompiler/lib/GenXOpts/CMTrans/GenXTrampolineInsertion.cpp

@@ -103,6 +103,8 @@ void GenXTrampolineInsertion::visitFunction(Function &F) {
     return;
   if (vc::isKernel(&F))
     return;
+  if (vc::isCMCallable(F))
+    return;
 
   if (!F.hasLocalLinkage()) {
     ExternalFuncs.push_back(&F);