AMDGPU: Set implicit kernarg size to be of 256 bytes for code object version 5

[cfang]

Summary

If implicitarg_ptr intrinsic is not used, set implicit kernarg size to 0, otherwise
set it to 256 bytes for code object version 5 (and beyond).

[arsenm]

This can be tested in the existing llvm/test/CodeGen/AMDGPU/llvm.amdgcn.implicitarg.ptr.ll

[cfang]

In D123262#3434565, @arsenm wrote:

This can be tested in the existing llvm/test/CodeGen/AMDGPU/llvm.amdgcn.implicitarg.ptr.ll

This will make things much complicated since version 5 will generates quite different code from version 2, also
the dumped variable names are different. Maybe we should only check the kernarg size for version 5.

[cfang]

update LIT test

[arsenm]

llvm/test/CodeGen/AMDGPU/llvm.amdgcn.implicitarg.ptr.ll

5

This is broken. You need to add back the GCN check prefix

[cfang]

llvm/test/CodeGen/AMDGPU/llvm.amdgcn.implicitarg.ptr.ll

5

Can you tell how this is broken? It passed the test for my check.
The problem is that, if we add back the GCN check prefix, the COV5 check won't be able to check the label (When I add prefix to COV5 cases, the test will fail GCN check because COV5 is quite different).

[cfang]

For the LIT test, add back the GCN check prefix. For the GCN checks that are common to code object version 2 and MESA but different from code object version 5, we split the checks to HSA (version 2) and MESA.

llvm/lib/Target/AMDGPU/AMDGPUSubtarget.cpp

unsigned AMDGPUSubtarget::getImplicitArgNumBytes(const Function &F) const {
   // used, even if the ABI implies we need them.
   if (F.hasFnAttribute("amdgpu-no-implicitarg-ptr"))
     return 0;
 
   if (isMesaKernel(F))
     return 16;
 
   // Assume all implicit inputs are used by default
-  return AMDGPU::getIntegerAttribute(F, "amdgpu-implicitarg-num-bytes", 56);
+  unsigned NBytes = (AMDGPU::getAmdhsaCodeObjectVersion() >= 5) ? 256 : 56;
+  return AMDGPU::getIntegerAttribute(F, "amdgpu-implicitarg-num-bytes", NBytes);
 }
 
 uint64_t AMDGPUSubtarget::getExplicitKernArgSize(const Function &F,
                                                  Align &MaxAlign) const {
   assert(F.getCallingConv() == CallingConv::AMDGPU_KERNEL ||
          F.getCallingConv() == CallingConv::SPIR_KERNEL);
 
   const DataLayout &DL = F.getParent()->getDataLayout();

llvm/test/CodeGen/AMDGPU/llvm.amdgcn.implicitarg.ptr.ll

 ; RUN: llc -mtriple=amdgcn-amd-amdhsa --amdhsa-code-object-version=2 -mcpu=kaveri -verify-machineinstrs < %s | FileCheck -check-prefixes=GCN,HSA %s
+; RUN: llc -mtriple=amdgcn-amd-amdhsa --amdhsa-code-object-version=5 -mcpu=kaveri -verify-machineinstrs < %s | FileCheck -check-prefixes=GCN,COV5 %s
 ; RUN: llc -mtriple=amdgcn-mesa-mesa3d -mcpu=tahiti -verify-machineinstrs < %s | FileCheck -check-prefixes=GCN,MESA %s
 
 ; GCN-LABEL: {{^}}kernel_implicitarg_ptr_empty:
 ; HSA: enable_sgpr_kernarg_segment_ptr = 1
 ; HSA: kernarg_segment_byte_size = 56
 ; HSA: kernarg_segment_alignment = 4
 
 ; MESA: enable_sgpr_kernarg_segment_ptr = 1
 ; MESA: kernarg_segment_byte_size = 16
 ; MESA: kernarg_segment_alignment = 4
 
 ; HSA: s_load_dword s0, s[4:5], 0x0
+
+; COV5: .amdhsa_kernarg_size 256
 define amdgpu_kernel void @kernel_implicitarg_ptr_empty() #0 {
   %implicitarg.ptr = call i8 addrspace(4)* @llvm.amdgcn.implicitarg.ptr()
   %cast = bitcast i8 addrspace(4)* %implicitarg.ptr to i32 addrspace(4)*
   %load = load volatile i32, i32 addrspace(4)* %cast
   ret void
 }
 
 ; GCN-LABEL: {{^}}kernel_implicitarg_ptr_empty_0implicit:
 ; HSA: enable_sgpr_kernarg_segment_ptr = 0
 ; HSA: kernarg_segment_byte_size = 0
 ; HSA: kernarg_segment_alignment = 4
 
 ; MESA: enable_sgpr_kernarg_segment_ptr = 1
 ; MESA: kernarg_segment_byte_size = 16
 ; MESA: kernarg_segment_alignment = 4
 
 ; HSA: s_mov_b64 [[NULL:s\[[0-9]+:[0-9]+\]]], 0{{$}}
 ; HSA: s_load_dword s0, [[NULL]], 0x0
 
 ; MESA: s_load_dword s0, s[4:5], 0x0
+
+; COV5: .amdhsa_kernarg_size 0
 define amdgpu_kernel void @kernel_implicitarg_ptr_empty_0implicit() #3 {
   %implicitarg.ptr = call i8 addrspace(4)* @llvm.amdgcn.implicitarg.ptr()
   %cast = bitcast i8 addrspace(4)* %implicitarg.ptr to i32 addrspace(4)*
   %load = load volatile i32, i32 addrspace(4)* %cast
   ret void
 }
 
 ; GCN-LABEL: {{^}}opencl_kernel_implicitarg_ptr_empty:
-; GCN: enable_sgpr_kernarg_segment_ptr = 1
 
+; HSA: enable_sgpr_kernarg_segment_ptr = 1
 ; HSA: kernarg_segment_byte_size = 48
 ; HSA: kernarg_segment_alignment = 4
 
+; MESA: enable_sgpr_kernarg_segment_ptr = 1
 ; MESA: kernarg_segment_byte_size = 16
 ; MESA: kernarg_segment_alignment = 4
 
 ; HSA: s_load_dword s0, s[4:5], 0x0
+
+; COV5: .amdhsa_kernarg_size 48
 define amdgpu_kernel void @opencl_kernel_implicitarg_ptr_empty() #1 {
   %implicitarg.ptr = call i8 addrspace(4)* @llvm.amdgcn.implicitarg.ptr()
   %cast = bitcast i8 addrspace(4)* %implicitarg.ptr to i32 addrspace(4)*
   %load = load volatile i32, i32 addrspace(4)* %cast
   ret void
 }
 
 ; GCN-LABEL: {{^}}kernel_implicitarg_ptr:
-; GCN: enable_sgpr_kernarg_segment_ptr = 1
 
+; HSA: enable_sgpr_kernarg_segment_ptr = 1
 ; HSA: kernarg_segment_byte_size = 168
 ; HSA: kernarg_segment_alignment = 4
 
+; MESA: enable_sgpr_kernarg_segment_ptr = 1
 ; MESA: kernarg_segment_byte_size = 128
 ; MESA: kernarg_segment_alignment = 4
 
 ; HSA: s_load_dword s0, s[4:5], 0x1c
+
+; COV5: .amdhsa_kernarg_size 368
 define amdgpu_kernel void @kernel_implicitarg_ptr([112 x i8]) #0 {
   %implicitarg.ptr = call i8 addrspace(4)* @llvm.amdgcn.implicitarg.ptr()
   %cast = bitcast i8 addrspace(4)* %implicitarg.ptr to i32 addrspace(4)*
   %load = load volatile i32, i32 addrspace(4)* %cast
   ret void
 }
 
 ; GCN-LABEL: {{^}}opencl_kernel_implicitarg_ptr:
-; GCN: enable_sgpr_kernarg_segment_ptr = 1
 
+; HSA: enable_sgpr_kernarg_segment_ptr = 1
 ; HSA: kernarg_segment_byte_size = 160
 ; HSA: kernarg_segment_alignment = 4
 
+; MESA: enable_sgpr_kernarg_segment_ptr = 1
 ; MESA: kernarg_segment_byte_size = 128
 ; MESA: kernarg_segment_alignment = 4
 
 ; HSA: s_load_dword s0, s[4:5], 0x1c
+
+; COV5: .amdhsa_kernarg_size 160
 define amdgpu_kernel void @opencl_kernel_implicitarg_ptr([112 x i8]) #1 {
   %implicitarg.ptr = call i8 addrspace(4)* @llvm.amdgcn.implicitarg.ptr()
   %cast = bitcast i8 addrspace(4)* %implicitarg.ptr to i32 addrspace(4)*
   %load = load volatile i32, i32 addrspace(4)* %cast
   ret void
 }
 
 ; GCN-LABEL: {{^}}func_implicitarg_ptr:

 ; HSA: kernarg_segment_alignment = 4
 
 ; MESA: enable_sgpr_kernarg_segment_ptr = 1
 ; MESA: kernarg_segment_byte_size = 16
 ; MESA: kernarg_segment_alignment = 4
 
 ; GCN: s_mov_b64 s[8:9], s[4:5]
 ; GCN: s_swappc_b64
+
+; COV5: .amdhsa_kernarg_size 256
 define amdgpu_kernel void @kernel_call_implicitarg_ptr_func_empty() #0 {
   call void @func_implicitarg_ptr()
   ret void
 }
 
 ; GCN-LABEL: {{^}}kernel_call_implicitarg_ptr_func_empty_implicit0:
 ; HSA: enable_sgpr_kernarg_segment_ptr = 0
 ; HSA: kernarg_segment_byte_size = 0
 ; HSA: kernarg_segment_alignment = 4
 
 ; MESA: enable_sgpr_kernarg_segment_ptr = 1
 ; MESA: kernarg_segment_byte_size = 16
 ; MESA: kernarg_segment_alignment = 4
 
 ; HSA: s_mov_b64 s[8:9], 0{{$}}
 ; MESA: s_mov_b64 s[8:9], s[4:5]{{$}}
 ; GCN: s_swappc_b64
+
+; COV5: .amdhsa_kernarg_size 0
 define amdgpu_kernel void @kernel_call_implicitarg_ptr_func_empty_implicit0() #3 {
   call void @func_implicitarg_ptr()
   ret void
 }
 
 ; GCN-LABEL: {{^}}opencl_kernel_call_implicitarg_ptr_func_empty:
-; GCN: enable_sgpr_kernarg_segment_ptr = 1
+; HSA: enable_sgpr_kernarg_segment_ptr = 1
 ; HSA: kernarg_segment_byte_size = 48
 ; HSA: kernarg_segment_alignment = 4
+; MESA: enable_sgpr_kernarg_segment_ptr = 1
 ; MESA: kernarg_segment_byte_size = 16
 ; GCN: s_mov_b64 s[8:9], s[4:5]
 ; GCN-NOT: s4
 ; GCN-NOT: s5
 ; GCN: s_swappc_b64
+
+; COV5: .amdhsa_kernarg_size 48
 define amdgpu_kernel void @opencl_kernel_call_implicitarg_ptr_func_empty() #1 {
   call void @func_implicitarg_ptr()
   ret void
 }
 
 ; GCN-LABEL: {{^}}kernel_call_implicitarg_ptr_func:
-; GCN: enable_sgpr_kernarg_segment_ptr = 1
+; HSA: enable_sgpr_kernarg_segment_ptr = 1
 ; HSA: kernarg_segment_byte_size = 168
 ; HSA: kernarg_segment_alignment = 4
 
+; MESA: enable_sgpr_kernarg_segment_ptr = 1
 ; MESA: kernarg_segment_byte_size = 128
 ; MESA: kernarg_segment_alignment = 4
 
 ; HSA: s_add_u32 s8, s4, 0x70
 ; MESA: s_add_u32 s8, s4, 0x70
 
 ; GCN: s_addc_u32 s9, s5, 0{{$}}
 ; GCN: s_swappc_b64
+
+; COV5: .amdhsa_kernarg_size 368
 define amdgpu_kernel void @kernel_call_implicitarg_ptr_func([112 x i8]) #0 {
   call void @func_implicitarg_ptr()
   ret void
 }
 
 ; GCN-LABEL: {{^}}opencl_kernel_call_implicitarg_ptr_func:
-; GCN: enable_sgpr_kernarg_segment_ptr = 1
+; HSA: enable_sgpr_kernarg_segment_ptr = 1
 ; HSA: kernarg_segment_byte_size = 160
 ; HSA: kernarg_segment_alignment = 4
+; MESA: enable_sgpr_kernarg_segment_ptr = 1
 ; MESA: kernarg_segment_byte_size = 128
 ; MESA: kernarg_segment_alignment = 4
 
 ; GCN: s_add_u32 s8, s4, 0x70
 ; GCN: s_addc_u32 s9, s5, 0{{$}}
 ; GCN: s_swappc_b64
+
+; COV5: .amdhsa_kernarg_size 160
 define amdgpu_kernel void @opencl_kernel_call_implicitarg_ptr_func([112 x i8]) #1 {
   call void @func_implicitarg_ptr()
   ret void
 }
 
 ; GCN-LABEL: {{^}}func_call_implicitarg_ptr_func:
 ; GCN-NOT: s8
 ; GCN-NOT: s9

 ; GCN: s_swappc_b64
 define amdgpu_kernel void @kernel_call_kernarg_implicitarg_ptr_func([112 x i8]) #0 {
   call void @func_kernarg_implicitarg_ptr()
   ret void
 }
 
 ; GCN-LABEL: {{^}}kernel_implicitarg_no_struct_align_padding:
 ; HSA: kernarg_segment_byte_size = 120
+; HSA: kernarg_segment_alignment = 6
 ; MESA: kernarg_segment_byte_size = 84
-; GCN: kernarg_segment_alignment = 6
+; MESA: kernarg_segment_alignment = 6
+
+; COV5: .amdhsa_kernarg_size 120
 define amdgpu_kernel void @kernel_implicitarg_no_struct_align_padding(<16 x i32>, i32) #1 {
   %implicitarg.ptr = call i8 addrspace(4)* @llvm.amdgcn.implicitarg.ptr()
   %cast = bitcast i8 addrspace(4)* %implicitarg.ptr to i32 addrspace(4)*
   %load = load volatile i32, i32 addrspace(4)* %cast
   ret void
 }
 
-
 ; HSA-LABEL: Kernels:
 ; HSA-LABEL: - Name:            kernel_implicitarg_ptr_empty
 ; HSA: CodeProps:
 ; HSA: KernargSegmentSize: 56
 ; HSA: KernargSegmentAlign: 8
 
 ; HSA-LABEL: - Name:            kernel_implicitarg_ptr_empty_0implicit
 ; HSA: KernargSegmentSize: 0

 ; HSA-LABEL: - Name:            kernel_call_kernarg_implicitarg_ptr_func
 ; HSA: KernargSegmentSize: 168
 ; HSA: KernargSegmentAlign: 8
 
 ; HSA-LABEL: - Name:            kernel_implicitarg_no_struct_align_padding
 ; HSA: KernargSegmentSize: 120
 ; HSA: KernargSegmentAlign: 64
 
+; COV5-LABEL:   amdhsa.kernels:
+; COV5:         .kernarg_segment_align: 8
+; COV5-NEXT:    .kernarg_segment_size: 256
+; COV5-LABEL:   .name:           kernel_implicitarg_ptr_empty
+
+; COV5:         .kernarg_segment_align: 4
+; COV5-NEXT:    .kernarg_segment_size: 0
+; COV5-LABEL:   .name:           kernel_implicitarg_ptr_empty_0implicit
+
+; COV5:         .kernarg_segment_align: 8
+; COV5-NEXT:    .kernarg_segment_size: 48
+; COV5-LABEL:   .name:           opencl_kernel_implicitarg_ptr_empty
+
+; COV5:         .kernarg_segment_align: 8
+; COV5-NEXT:    .kernarg_segment_size: 368
+; COV5-LABEL:   .name:           kernel_implicitarg_ptr
+
+; COV5:         .kernarg_segment_align: 8
+; COV5-NEXT:    .kernarg_segment_size: 160
+; COV5-LABEL:   .name:           opencl_kernel_implicitarg_ptr
+
+; COV5:         .kernarg_segment_align: 8
+; COV5-NEXT:    .kernarg_segment_size: 256
+; COV5-LABEL:   .name:           kernel_call_implicitarg_ptr_func_empty
+
+; COV5:         .kernarg_segment_align: 4
+; COV5-NEXT:    .kernarg_segment_size: 0
+; COV5-LABEL:   .name:           kernel_call_implicitarg_ptr_func_empty_implicit0
+
+; COV5:         .kernarg_segment_align: 8
+; COV5-NEXT:    .kernarg_segment_size: 48
+; COV5-LABEL:   .name:           opencl_kernel_call_implicitarg_ptr_func_empty
+
+; COV5:         .kernarg_segment_align: 8
+; COV5-NEXT:    .kernarg_segment_size: 368
+; COV5-LABEL:   .name:           kernel_call_implicitarg_ptr_func
+
+; COV5:         .kernarg_segment_align: 8
+; COV5-NEXT:    .kernarg_segment_size: 160
+; COV5-LABEL:   .name:           opencl_kernel_call_implicitarg_ptr_func
+
+; COV5:         .kernarg_segment_align: 8
+; COV5-NEXT:    .kernarg_segment_size: 368
+; COV5-LABEL:   .name:           kernel_call_kernarg_implicitarg_ptr_func
+
+; COV5:         .kernarg_segment_align: 64
+; COV5-NEXT:    .kernarg_segment_size: 120
+; COV5-LABEL:   .name:           kernel_implicitarg_no_struct_align_padding
+
 declare i8 addrspace(4)* @llvm.amdgcn.implicitarg.ptr() #2
 declare i8 addrspace(4)* @llvm.amdgcn.kernarg.segment.ptr() #2
 
 attributes #0 = { nounwind noinline }
 attributes #1 = { nounwind noinline "amdgpu-implicitarg-num-bytes"="48" }
 attributes #2 = { nounwind readnone speculatable }
 attributes #3 = { nounwind noinline "amdgpu-implicitarg-num-bytes"="0" }