[clang] [llvm] [AMDGPU] Adding the amdgpu-num-work-groups function attribute (PR #79035)

[Matt Arsenault via cfe-commits]

================
@@ -0,0 +1,84 @@
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 < %s | FileCheck %s
+
+; Attribute not specified.
+; CHECK-LABEL: {{^}}empty_no_attribute:
+define amdgpu_kernel void @empty_no_attribute() {
+entry:
+  ret void
+}
+
+; Ignore if number of work groups for x dimension is 0.
+; CHECK-LABEL: {{^}}empty_max_num_work_groups_x0:
+define amdgpu_kernel void @empty_max_num_work_groups_x0() #0 {
+entry:
+  ret void
+}
+attributes #0 = {"amdgpu-max-num-work-groups"="0,2,3"}
+
+; Ignore if number of work groups for y dimension is 0.
+; CHECK-LABEL: {{^}}empty_max_num_work_groups_y0:
+define amdgpu_kernel void @empty_max_num_work_groups_y0() #1 {
+entry:
+  ret void
+}
+attributes #1 = {"amdgpu-max-num-work-groups"="1,0,3"}
+
+; Ignore if number of work groups for z dimension is 0.
+; CHECK-LABEL: {{^}}empty_max_num_work_groups_z0:
+define amdgpu_kernel void @empty_max_num_work_groups_z0() #2 {
+entry:
+  ret void
+}
+attributes #2 = {"amdgpu-max-num-work-groups"="1,2,0"}
+
+; CHECK-LABEL: {{^}}empty_max_num_work_groups_1_2_3:
+define amdgpu_kernel void @empty_max_num_work_groups_1_2_3() #3 {
+entry:
+  ret void
+}
+attributes #3 = {"amdgpu-max-num-work-groups"="1,2,3"}
+
+; CHECK-LABEL: {{^}}empty_max_num_work_groups_1024_1024_1024:
+define amdgpu_kernel void @empty_max_num_work_groups_1024_1024_1024() #4 {
+entry:
+  ret void
+}
+attributes #4 = {"amdgpu-max-num-work-groups"="1024,1024,1024"}
+
----------------
arsenm wrote:

Check some negative, and hex values which I believe will be handled correctly by the parser

https://github.com/llvm/llvm-project/pull/79035