[clang] [Clang][AMDGPU] Add a builtin for llvm.amdgcn.make.buffer.rsrc intrinsic (PR #95276)

[Shilei Tian via cfe-commits]

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@@ -0,0 +1,95 @@
+// NOTE: Assertions have been autogenerated by utils/update_cc_test_checks.py
+// REQUIRES: amdgpu-registered-target
+// RUN: %clang_cc1 -triple amdgcn-unknown-unknown -cl-std=CL2.0 -target-cpu verde -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -triple amdgcn-unknown-unknown -cl-std=CL2.0 -target-cpu tonga -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -triple amdgcn-unknown-unknown -cl-std=CL2.0 -target-cpu gfx1100 -emit-llvm -o - %s | FileCheck %s
+
+// CHECK-LABEL: @test_amdgcn_make_buffer_rsrc_p0(
+// CHECK-NEXT:  entry:
+// CHECK-NEXT:    [[TMP0:%.*]] = tail call ptr addrspace(8) @llvm.amdgcn.make.buffer.rsrc.p0(ptr [[P:%.*]], i16 [[STRIDE:%.*]], i32 [[NUM:%.*]], i32 [[FLAGS:%.*]])
+// CHECK-NEXT:    ret ptr addrspace(8) [[TMP0]]
+//
+__buffer_rsrc_t test_amdgcn_make_buffer_rsrc_p0(void *p, short stride, int num, int flags) {
+  return __builtin_amdgcn_make_buffer_rsrc(p, stride, num, flags);
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shiltian wrote:

No, we don't allow to have that. Per the discussion with @arsenm , `__buffer_rsrc_t` is a sizeless target opaque type. It can't be used in anywhere that requires its size to be known.

https://github.com/llvm/llvm-project/pull/95276