libclc: Stop using r600 asm intrinsic declarations for amdgcn (llvm#181975)

Really the workitem functions should all be moved to generic code
and use gpuintrin.h. These implementations were copied from there.

Author: arsenm

libclc/opencl/lib/amdgcn/workitem/get_local_size.cl

@@ -8,18 +8,14 @@
 
 #include <clc/opencl/opencl-base.h>
 
-uint __clc_amdgcn_get_local_size_x(void) __asm("llvm.r600.read.local.size.x");
-uint __clc_amdgcn_get_local_size_y(void) __asm("llvm.r600.read.local.size.y");
-uint __clc_amdgcn_get_local_size_z(void) __asm("llvm.r600.read.local.size.z");
-
 _CLC_DEF _CLC_OVERLOAD size_t get_local_size(uint dim) {
   switch (dim) {
   case 0:
-    return __clc_amdgcn_get_local_size_x();
+    return __builtin_amdgcn_workgroup_size_x();
   case 1:
-    return __clc_amdgcn_get_local_size_y();
+    return __builtin_amdgcn_workgroup_size_y();
   case 2:
-    return __clc_amdgcn_get_local_size_z();
+    return __builtin_amdgcn_workgroup_size_z();
   default:
     return 1;
   }

libclc/opencl/lib/amdgcn/workitem/get_num_groups.cl

@@ -8,18 +8,14 @@
 
 #include <clc/opencl/opencl-base.h>
 
-uint __clc_amdgcn_get_num_groups_x(void) __asm("llvm.r600.read.ngroups.x");
-uint __clc_amdgcn_get_num_groups_y(void) __asm("llvm.r600.read.ngroups.y");
-uint __clc_amdgcn_get_num_groups_z(void) __asm("llvm.r600.read.ngroups.z");
-
 _CLC_DEF _CLC_OVERLOAD size_t get_num_groups(uint dim) {
   switch (dim) {
   case 0:
-    return __clc_amdgcn_get_num_groups_x();
+    return __builtin_amdgcn_grid_size_x() / __builtin_amdgcn_workgroup_size_x();
   case 1:
-    return __clc_amdgcn_get_num_groups_y();
+    return __builtin_amdgcn_grid_size_y() / __builtin_amdgcn_workgroup_size_y();
   case 2:
-    return __clc_amdgcn_get_num_groups_z();
+    return __builtin_amdgcn_grid_size_z() / __builtin_amdgcn_workgroup_size_z();
   default:
     return 1;
   }