[AMDGPU][Verifier] Mark calls to entry functions as invalid in the IR verifier (#134910)

Author: shiltian

llvm/include/llvm/IR/CallingConv.h

@@ -290,6 +290,27 @@ namespace CallingConv {
 
 } // end namespace CallingConv
 
+/// \return true if the calling convention allows the function to be called
+/// directly or indirectly via a call-like instruction.
+constexpr bool isCallableCC(CallingConv::ID CC) {
+  switch (CC) {
+  case CallingConv::AMDGPU_CS_Chain:
+  case CallingConv::AMDGPU_CS_ChainPreserve:
+  case CallingConv::AMDGPU_CS:
+  case CallingConv::AMDGPU_ES:
+  case CallingConv::AMDGPU_GS:
+  case CallingConv::AMDGPU_HS:
+  case CallingConv::AMDGPU_KERNEL:
+  case CallingConv::AMDGPU_LS:
+  case CallingConv::AMDGPU_PS:
+  case CallingConv::AMDGPU_VS:
+  case CallingConv::SPIR_KERNEL:
+    return false;
+  default:
+    return true;
+  }
+}
+
 } // end namespace llvm
 
 #endif // LLVM_IR_CALLINGCONV_H

llvm/lib/IR/Verifier.cpp

@@ -3596,14 +3596,9 @@ void Verifier::visitCallBase(CallBase &Call) {
     Check(Callee->getValueType() == FTy,
           "Intrinsic called with incompatible signature", Call);
 
-  // Disallow calls to functions with the amdgpu_cs_chain[_preserve] calling
-  // convention.
-  auto CC = Call.getCallingConv();
-  Check(CC != CallingConv::AMDGPU_CS_Chain &&
-            CC != CallingConv::AMDGPU_CS_ChainPreserve,
-        "Direct calls to amdgpu_cs_chain/amdgpu_cs_chain_preserve functions "
-        "not allowed. Please use the @llvm.amdgpu.cs.chain intrinsic instead.",
-        Call);
+  // Verify if the calling convention of the callee is callable.
+  Check(isCallableCC(Call.getCallingConv()),
+        "calling convention does not permit calls", Call);
 
   // Disallow passing/returning values with alignment higher than we can
   // represent.

llvm/test/Bitcode/calling-conventions.3.2.ll

@@ -80,12 +80,6 @@ define void @call_cc10 () {
   ret void
 }
 
-define void @call_spir_kernel() {
-; CHECK: call spir_kernel void @spir_kernel
-  call spir_kernel void @spir_kernel()
-  ret void
-}
-
 define void @call_spir_func() {
 ; CHECK: call spir_func void @spir_func
   call spir_func void @spir_func()

llvm/test/Bitcode/calling-conventions.3.2.ll.bc

@@ -849,21 +849,6 @@ define amdgpu_kernel void @calls_intrin_ascast_cc_kernel(ptr addrspace(3) %ptr)
   ret void
 }
 
-define amdgpu_kernel void @call_calls_intrin_ascast_cc_kernel(ptr addrspace(3) %ptr) {
-; GFX9-LABEL: define amdgpu_kernel void @call_calls_intrin_ascast_cc_kernel(
-; GFX9-SAME: ptr addrspace(3) [[PTR:%.*]]) #[[ATTR1]] {
-; GFX9-NEXT:    call void @calls_intrin_ascast_cc_kernel(ptr addrspace(3) [[PTR]])
-; GFX9-NEXT:    ret void
-;
-; GFX10-LABEL: define amdgpu_kernel void @call_calls_intrin_ascast_cc_kernel(
-; GFX10-SAME: ptr addrspace(3) [[PTR:%.*]]) #[[ATTR1]] {
-; GFX10-NEXT:    call void @calls_intrin_ascast_cc_kernel(ptr addrspace(3) [[PTR]])
-; GFX10-NEXT:    ret void
-;
-  call void @calls_intrin_ascast_cc_kernel(ptr addrspace(3) %ptr)
-  ret void
-}
-
 define amdgpu_kernel void @with_inline_asm() {
 ; GFX9-LABEL: define amdgpu_kernel void @with_inline_asm(
 ; GFX9-SAME: ) #[[ATTR3]] {

llvm/test/CodeGen/AMDGPU/attributor-flatscratchinit.ll

@@ -8,6 +8,5 @@ define spir_func void @foo() {
 
 define spir_kernel void @bar() {
         call spir_func void @foo( )
-        call spir_kernel void @bar( )
         ret void
 }

llvm/test/CodeGen/AMDGPU/call-to-kernel-undefined.ll

@@ -217,26 +217,3 @@ define amdgpu_cs_chain_preserve void @preallocated_cc_amdgpu_cs_chain_preserve(p
 define amdgpu_cs_chain_preserve void @inalloca_cc_amdgpu_cs_chain_preserve(ptr inalloca(i32) %ptr) {
   ret void
 }
-
-declare amdgpu_cs_chain void @amdgpu_cs_chain_call_target()
-declare amdgpu_cs_chain_preserve void @amdgpu_cs_chain_preserve_call_target()
-
-define amdgpu_cs_chain void @cant_call_amdgpu_cs_chain_functions(ptr %f) {
-  ; CHECK: Direct calls to amdgpu_cs_chain/amdgpu_cs_chain_preserve functions not allowed. Please use the @llvm.amdgpu.cs.chain intrinsic instead.
-  ; CHECK-NEXT: call amdgpu_cs_chain
-  call amdgpu_cs_chain void @amdgpu_cs_chain_call_target()
-
-  ; CHECK: Direct calls to amdgpu_cs_chain/amdgpu_cs_chain_preserve functions not allowed. Please use the @llvm.amdgpu.cs.chain intrinsic instead.
-  ; CHECK-NEXT: call amdgpu_cs_chain_preserve
-  call amdgpu_cs_chain_preserve void @amdgpu_cs_chain_preserve_call_target()
-
-  ; CHECK: Direct calls to amdgpu_cs_chain/amdgpu_cs_chain_preserve functions not allowed. Please use the @llvm.amdgpu.cs.chain intrinsic instead.
-  ; CHECK-NEXT: call amdgpu_cs_chain
-  call amdgpu_cs_chain void %f()
-
-  ; CHECK: Direct calls to amdgpu_cs_chain/amdgpu_cs_chain_preserve functions not allowed. Please use the @llvm.amdgpu.cs.chain intrinsic instead.
-  ; CHECK-NEXT: call amdgpu_cs_chain
-  call amdgpu_cs_chain_preserve void %f()
-
-  ret void
-}