Replace fragile CHECK-NOT with -implicit-check-not

Author: slinder1

llvm/test/CodeGen/AMDGPU/preload-implicit-kernargs-debug-info.ll

@@ -1,7 +1,10 @@
-; RUN: opt -mtriple=amdgcn-amd-amdhsa -mcpu=gfx940 -passes='amdgpu-attributor,function(amdgpu-lower-kernel-arguments)' -amdgpu-kernarg-preload-count=16 -S < %s 2>&1 | FileCheck %s
+; RUN: opt -mtriple=amdgcn-amd-amdhsa -mcpu=gfx940 -passes='amdgpu-attributor,function(amdgpu-lower-kernel-arguments)' -amdgpu-kernarg-preload-count=16 -S < %s 2>&1 \
+; RUN: | FileCheck -implicit-check-not='declare {{.*}} !dbg' %s
+
+; The real test is via the -implicit-check-not, which confirms we do not
+; leave behind a declaration which references the same DISubprogram metadata.
 
 ; CHECK: define amdgpu_kernel void @preload_block_count_x{{.*}} !dbg ![[#]]
-; CHECK-NOT: declare void @0{{.*}} !dbg ![[#]]
 
 define amdgpu_kernel void @preload_block_count_x(ptr addrspace(1) %out) !dbg !4 !max_work_group_size !7 {
   %imp_arg_ptr = call ptr addrspace(4) @llvm.amdgcn.implicitarg.ptr()