Files
clang-p2996/llvm/test/CodeGen/AMDGPU/stack-realign-kernel.ll
Diana Picus 130080fab1 [AMDGPU] Skip register uses in AMDGPUResourceUsageAnalysis (#133242)
Don't count register uses when determining the maximum number of
registers used by a function. Count only the defs. This is really an
underestimate of the true register usage, but in practice that's not
a problem because if a function uses a register, then it has either
defined it earlier, or some other function that executed before has
defined it.

In particular, the register counts are used:
1. When launching an entry function - in which case we're safe because
   the register counts of the entry function will include the register
   counts of all callees.
2. At function boundaries in dynamic VGPR mode. In this case it's safe
   because whenever we set the new VGPR allocation we take into account
   the outgoing_vgpr_count set by the middle-end.

The main advantage of doing this is that the artificial VGPR arguments
used only for preserving the inactive lanes when using the
llvm.amdgcn.init.whole.wave intrinsic are no longer counted. This
enables us to allocate only the registers we need in dynamic VGPR mode.

---------

Co-authored-by: Thomas Symalla <5754458+tsymalla@users.noreply.github.com>
2025-06-03 11:20:48 +02:00

345 lines
15 KiB
LLVM

; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=fiji < %s | FileCheck -check-prefix=VI %s
; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 < %s | FileCheck -check-prefix=GFX9 %s
; Make sure the stack is never realigned for entry functions.
define amdgpu_kernel void @max_alignment_128() #0 {
; VI-LABEL: max_alignment_128:
; VI: ; %bb.0:
; VI-NEXT: s_add_u32 s0, s0, s17
; VI-NEXT: s_addc_u32 s1, s1, 0
; VI-NEXT: v_mov_b32_e32 v0, 3
; VI-NEXT: buffer_store_byte v0, off, s[0:3], 0
; VI-NEXT: s_waitcnt vmcnt(0)
; VI-NEXT: v_mov_b32_e32 v0, 9
; VI-NEXT: buffer_store_dword v0, off, s[0:3], 0 offset:128
; VI-NEXT: s_waitcnt vmcnt(0)
; VI-NEXT: s_endpgm
; VI-NEXT: .section .rodata,"a"
; VI-NEXT: .p2align 6
; VI-NEXT: .amdhsa_kernel max_alignment_128
; VI-NEXT: .amdhsa_group_segment_fixed_size 0
; VI-NEXT: .amdhsa_private_segment_fixed_size 256
; VI-NEXT: .amdhsa_kernarg_size 56
; VI-NEXT: .amdhsa_user_sgpr_count 14
; VI-NEXT: .amdhsa_user_sgpr_private_segment_buffer 1
; VI-NEXT: .amdhsa_user_sgpr_dispatch_ptr 1
; VI-NEXT: .amdhsa_user_sgpr_queue_ptr 1
; VI-NEXT: .amdhsa_user_sgpr_kernarg_segment_ptr 1
; VI-NEXT: .amdhsa_user_sgpr_dispatch_id 1
; VI-NEXT: .amdhsa_user_sgpr_flat_scratch_init 1
; VI-NEXT: .amdhsa_user_sgpr_private_segment_size 0
; VI-NEXT: .amdhsa_system_sgpr_private_segment_wavefront_offset 1
; VI-NEXT: .amdhsa_system_sgpr_workgroup_id_x 1
; VI-NEXT: .amdhsa_system_sgpr_workgroup_id_y 1
; VI-NEXT: .amdhsa_system_sgpr_workgroup_id_z 1
; VI-NEXT: .amdhsa_system_sgpr_workgroup_info 0
; VI-NEXT: .amdhsa_system_vgpr_workitem_id 2
; VI-NEXT: .amdhsa_next_free_vgpr 3
; VI-NEXT: .amdhsa_next_free_sgpr 18
; VI-NEXT: .amdhsa_reserve_vcc 0
; VI-NEXT: .amdhsa_reserve_flat_scratch 0
; VI-NEXT: .amdhsa_float_round_mode_32 0
; VI-NEXT: .amdhsa_float_round_mode_16_64 0
; VI-NEXT: .amdhsa_float_denorm_mode_32 3
; VI-NEXT: .amdhsa_float_denorm_mode_16_64 3
; VI-NEXT: .amdhsa_dx10_clamp 1
; VI-NEXT: .amdhsa_ieee_mode 1
; VI-NEXT: .amdhsa_exception_fp_ieee_invalid_op 0
; VI-NEXT: .amdhsa_exception_fp_denorm_src 0
; VI-NEXT: .amdhsa_exception_fp_ieee_div_zero 0
; VI-NEXT: .amdhsa_exception_fp_ieee_overflow 0
; VI-NEXT: .amdhsa_exception_fp_ieee_underflow 0
; VI-NEXT: .amdhsa_exception_fp_ieee_inexact 0
; VI-NEXT: .amdhsa_exception_int_div_zero 0
; VI-NEXT: .end_amdhsa_kernel
; VI-NEXT: .text
;
; GFX9-LABEL: max_alignment_128:
; GFX9: ; %bb.0:
; GFX9-NEXT: s_add_u32 s0, s0, s17
; GFX9-NEXT: s_addc_u32 s1, s1, 0
; GFX9-NEXT: v_mov_b32_e32 v0, 3
; GFX9-NEXT: buffer_store_byte v0, off, s[0:3], 0
; GFX9-NEXT: s_waitcnt vmcnt(0)
; GFX9-NEXT: v_mov_b32_e32 v0, 9
; GFX9-NEXT: buffer_store_dword v0, off, s[0:3], 0 offset:128
; GFX9-NEXT: s_waitcnt vmcnt(0)
; GFX9-NEXT: s_endpgm
; GFX9-NEXT: .section .rodata,"a"
; GFX9-NEXT: .p2align 6
; GFX9-NEXT: .amdhsa_kernel max_alignment_128
; GFX9-NEXT: .amdhsa_group_segment_fixed_size 0
; GFX9-NEXT: .amdhsa_private_segment_fixed_size 256
; GFX9-NEXT: .amdhsa_kernarg_size 56
; GFX9-NEXT: .amdhsa_user_sgpr_count 14
; GFX9-NEXT: .amdhsa_user_sgpr_private_segment_buffer 1
; GFX9-NEXT: .amdhsa_user_sgpr_dispatch_ptr 1
; GFX9-NEXT: .amdhsa_user_sgpr_queue_ptr 1
; GFX9-NEXT: .amdhsa_user_sgpr_kernarg_segment_ptr 1
; GFX9-NEXT: .amdhsa_user_sgpr_dispatch_id 1
; GFX9-NEXT: .amdhsa_user_sgpr_flat_scratch_init 1
; GFX9-NEXT: .amdhsa_user_sgpr_private_segment_size 0
; GFX9-NEXT: .amdhsa_system_sgpr_private_segment_wavefront_offset 1
; GFX9-NEXT: .amdhsa_system_sgpr_workgroup_id_x 1
; GFX9-NEXT: .amdhsa_system_sgpr_workgroup_id_y 1
; GFX9-NEXT: .amdhsa_system_sgpr_workgroup_id_z 1
; GFX9-NEXT: .amdhsa_system_sgpr_workgroup_info 0
; GFX9-NEXT: .amdhsa_system_vgpr_workitem_id 2
; GFX9-NEXT: .amdhsa_next_free_vgpr 3
; GFX9-NEXT: .amdhsa_next_free_sgpr 18
; GFX9-NEXT: .amdhsa_reserve_vcc 0
; GFX9-NEXT: .amdhsa_reserve_flat_scratch 0
; GFX9-NEXT: .amdhsa_reserve_xnack_mask 1
; GFX9-NEXT: .amdhsa_float_round_mode_32 0
; GFX9-NEXT: .amdhsa_float_round_mode_16_64 0
; GFX9-NEXT: .amdhsa_float_denorm_mode_32 3
; GFX9-NEXT: .amdhsa_float_denorm_mode_16_64 3
; GFX9-NEXT: .amdhsa_dx10_clamp 1
; GFX9-NEXT: .amdhsa_ieee_mode 1
; GFX9-NEXT: .amdhsa_fp16_overflow 0
; GFX9-NEXT: .amdhsa_exception_fp_ieee_invalid_op 0
; GFX9-NEXT: .amdhsa_exception_fp_denorm_src 0
; GFX9-NEXT: .amdhsa_exception_fp_ieee_div_zero 0
; GFX9-NEXT: .amdhsa_exception_fp_ieee_overflow 0
; GFX9-NEXT: .amdhsa_exception_fp_ieee_underflow 0
; GFX9-NEXT: .amdhsa_exception_fp_ieee_inexact 0
; GFX9-NEXT: .amdhsa_exception_int_div_zero 0
; GFX9-NEXT: .end_amdhsa_kernel
; GFX9-NEXT: .text
%clutter = alloca i8, addrspace(5) ; Force non-zero offset for next alloca
store volatile i8 3, ptr addrspace(5) %clutter
%alloca.align = alloca i32, align 128, addrspace(5)
store volatile i32 9, ptr addrspace(5) %alloca.align, align 128
ret void
}
define amdgpu_kernel void @stackrealign_attr() #1 {
; VI-LABEL: stackrealign_attr:
; VI: ; %bb.0:
; VI-NEXT: s_add_u32 s0, s0, s17
; VI-NEXT: s_addc_u32 s1, s1, 0
; VI-NEXT: v_mov_b32_e32 v0, 3
; VI-NEXT: buffer_store_byte v0, off, s[0:3], 0
; VI-NEXT: s_waitcnt vmcnt(0)
; VI-NEXT: v_mov_b32_e32 v0, 9
; VI-NEXT: buffer_store_dword v0, off, s[0:3], 0 offset:4
; VI-NEXT: s_waitcnt vmcnt(0)
; VI-NEXT: s_endpgm
; VI-NEXT: .section .rodata,"a"
; VI-NEXT: .p2align 6
; VI-NEXT: .amdhsa_kernel stackrealign_attr
; VI-NEXT: .amdhsa_group_segment_fixed_size 0
; VI-NEXT: .amdhsa_private_segment_fixed_size 12
; VI-NEXT: .amdhsa_kernarg_size 56
; VI-NEXT: .amdhsa_user_sgpr_count 14
; VI-NEXT: .amdhsa_user_sgpr_private_segment_buffer 1
; VI-NEXT: .amdhsa_user_sgpr_dispatch_ptr 1
; VI-NEXT: .amdhsa_user_sgpr_queue_ptr 1
; VI-NEXT: .amdhsa_user_sgpr_kernarg_segment_ptr 1
; VI-NEXT: .amdhsa_user_sgpr_dispatch_id 1
; VI-NEXT: .amdhsa_user_sgpr_flat_scratch_init 1
; VI-NEXT: .amdhsa_user_sgpr_private_segment_size 0
; VI-NEXT: .amdhsa_system_sgpr_private_segment_wavefront_offset 1
; VI-NEXT: .amdhsa_system_sgpr_workgroup_id_x 1
; VI-NEXT: .amdhsa_system_sgpr_workgroup_id_y 1
; VI-NEXT: .amdhsa_system_sgpr_workgroup_id_z 1
; VI-NEXT: .amdhsa_system_sgpr_workgroup_info 0
; VI-NEXT: .amdhsa_system_vgpr_workitem_id 2
; VI-NEXT: .amdhsa_next_free_vgpr 3
; VI-NEXT: .amdhsa_next_free_sgpr 18
; VI-NEXT: .amdhsa_reserve_vcc 0
; VI-NEXT: .amdhsa_reserve_flat_scratch 0
; VI-NEXT: .amdhsa_float_round_mode_32 0
; VI-NEXT: .amdhsa_float_round_mode_16_64 0
; VI-NEXT: .amdhsa_float_denorm_mode_32 3
; VI-NEXT: .amdhsa_float_denorm_mode_16_64 3
; VI-NEXT: .amdhsa_dx10_clamp 1
; VI-NEXT: .amdhsa_ieee_mode 1
; VI-NEXT: .amdhsa_exception_fp_ieee_invalid_op 0
; VI-NEXT: .amdhsa_exception_fp_denorm_src 0
; VI-NEXT: .amdhsa_exception_fp_ieee_div_zero 0
; VI-NEXT: .amdhsa_exception_fp_ieee_overflow 0
; VI-NEXT: .amdhsa_exception_fp_ieee_underflow 0
; VI-NEXT: .amdhsa_exception_fp_ieee_inexact 0
; VI-NEXT: .amdhsa_exception_int_div_zero 0
; VI-NEXT: .end_amdhsa_kernel
; VI-NEXT: .text
;
; GFX9-LABEL: stackrealign_attr:
; GFX9: ; %bb.0:
; GFX9-NEXT: s_add_u32 s0, s0, s17
; GFX9-NEXT: s_addc_u32 s1, s1, 0
; GFX9-NEXT: v_mov_b32_e32 v0, 3
; GFX9-NEXT: buffer_store_byte v0, off, s[0:3], 0
; GFX9-NEXT: s_waitcnt vmcnt(0)
; GFX9-NEXT: v_mov_b32_e32 v0, 9
; GFX9-NEXT: buffer_store_dword v0, off, s[0:3], 0 offset:4
; GFX9-NEXT: s_waitcnt vmcnt(0)
; GFX9-NEXT: s_endpgm
; GFX9-NEXT: .section .rodata,"a"
; GFX9-NEXT: .p2align 6
; GFX9-NEXT: .amdhsa_kernel stackrealign_attr
; GFX9-NEXT: .amdhsa_group_segment_fixed_size 0
; GFX9-NEXT: .amdhsa_private_segment_fixed_size 12
; GFX9-NEXT: .amdhsa_kernarg_size 56
; GFX9-NEXT: .amdhsa_user_sgpr_count 14
; GFX9-NEXT: .amdhsa_user_sgpr_private_segment_buffer 1
; GFX9-NEXT: .amdhsa_user_sgpr_dispatch_ptr 1
; GFX9-NEXT: .amdhsa_user_sgpr_queue_ptr 1
; GFX9-NEXT: .amdhsa_user_sgpr_kernarg_segment_ptr 1
; GFX9-NEXT: .amdhsa_user_sgpr_dispatch_id 1
; GFX9-NEXT: .amdhsa_user_sgpr_flat_scratch_init 1
; GFX9-NEXT: .amdhsa_user_sgpr_private_segment_size 0
; GFX9-NEXT: .amdhsa_system_sgpr_private_segment_wavefront_offset 1
; GFX9-NEXT: .amdhsa_system_sgpr_workgroup_id_x 1
; GFX9-NEXT: .amdhsa_system_sgpr_workgroup_id_y 1
; GFX9-NEXT: .amdhsa_system_sgpr_workgroup_id_z 1
; GFX9-NEXT: .amdhsa_system_sgpr_workgroup_info 0
; GFX9-NEXT: .amdhsa_system_vgpr_workitem_id 2
; GFX9-NEXT: .amdhsa_next_free_vgpr 3
; GFX9-NEXT: .amdhsa_next_free_sgpr 18
; GFX9-NEXT: .amdhsa_reserve_vcc 0
; GFX9-NEXT: .amdhsa_reserve_flat_scratch 0
; GFX9-NEXT: .amdhsa_reserve_xnack_mask 1
; GFX9-NEXT: .amdhsa_float_round_mode_32 0
; GFX9-NEXT: .amdhsa_float_round_mode_16_64 0
; GFX9-NEXT: .amdhsa_float_denorm_mode_32 3
; GFX9-NEXT: .amdhsa_float_denorm_mode_16_64 3
; GFX9-NEXT: .amdhsa_dx10_clamp 1
; GFX9-NEXT: .amdhsa_ieee_mode 1
; GFX9-NEXT: .amdhsa_fp16_overflow 0
; GFX9-NEXT: .amdhsa_exception_fp_ieee_invalid_op 0
; GFX9-NEXT: .amdhsa_exception_fp_denorm_src 0
; GFX9-NEXT: .amdhsa_exception_fp_ieee_div_zero 0
; GFX9-NEXT: .amdhsa_exception_fp_ieee_overflow 0
; GFX9-NEXT: .amdhsa_exception_fp_ieee_underflow 0
; GFX9-NEXT: .amdhsa_exception_fp_ieee_inexact 0
; GFX9-NEXT: .amdhsa_exception_int_div_zero 0
; GFX9-NEXT: .end_amdhsa_kernel
; GFX9-NEXT: .text
%clutter = alloca i8, addrspace(5) ; Force non-zero offset for next alloca
store volatile i8 3, ptr addrspace(5) %clutter
%alloca.align = alloca i32, align 4, addrspace(5)
store volatile i32 9, ptr addrspace(5) %alloca.align, align 4
ret void
}
define amdgpu_kernel void @alignstack_attr() #2 {
; VI-LABEL: alignstack_attr:
; VI: ; %bb.0:
; VI-NEXT: s_add_u32 s0, s0, s17
; VI-NEXT: s_addc_u32 s1, s1, 0
; VI-NEXT: v_mov_b32_e32 v0, 3
; VI-NEXT: buffer_store_byte v0, off, s[0:3], 0
; VI-NEXT: s_waitcnt vmcnt(0)
; VI-NEXT: v_mov_b32_e32 v0, 9
; VI-NEXT: buffer_store_dword v0, off, s[0:3], 0 offset:4
; VI-NEXT: s_waitcnt vmcnt(0)
; VI-NEXT: s_endpgm
; VI-NEXT: .section .rodata,"a"
; VI-NEXT: .p2align 6
; VI-NEXT: .amdhsa_kernel alignstack_attr
; VI-NEXT: .amdhsa_group_segment_fixed_size 0
; VI-NEXT: .amdhsa_private_segment_fixed_size 128
; VI-NEXT: .amdhsa_kernarg_size 56
; VI-NEXT: .amdhsa_user_sgpr_count 14
; VI-NEXT: .amdhsa_user_sgpr_private_segment_buffer 1
; VI-NEXT: .amdhsa_user_sgpr_dispatch_ptr 1
; VI-NEXT: .amdhsa_user_sgpr_queue_ptr 1
; VI-NEXT: .amdhsa_user_sgpr_kernarg_segment_ptr 1
; VI-NEXT: .amdhsa_user_sgpr_dispatch_id 1
; VI-NEXT: .amdhsa_user_sgpr_flat_scratch_init 1
; VI-NEXT: .amdhsa_user_sgpr_private_segment_size 0
; VI-NEXT: .amdhsa_system_sgpr_private_segment_wavefront_offset 1
; VI-NEXT: .amdhsa_system_sgpr_workgroup_id_x 1
; VI-NEXT: .amdhsa_system_sgpr_workgroup_id_y 1
; VI-NEXT: .amdhsa_system_sgpr_workgroup_id_z 1
; VI-NEXT: .amdhsa_system_sgpr_workgroup_info 0
; VI-NEXT: .amdhsa_system_vgpr_workitem_id 2
; VI-NEXT: .amdhsa_next_free_vgpr 3
; VI-NEXT: .amdhsa_next_free_sgpr 18
; VI-NEXT: .amdhsa_reserve_vcc 0
; VI-NEXT: .amdhsa_reserve_flat_scratch 0
; VI-NEXT: .amdhsa_float_round_mode_32 0
; VI-NEXT: .amdhsa_float_round_mode_16_64 0
; VI-NEXT: .amdhsa_float_denorm_mode_32 3
; VI-NEXT: .amdhsa_float_denorm_mode_16_64 3
; VI-NEXT: .amdhsa_dx10_clamp 1
; VI-NEXT: .amdhsa_ieee_mode 1
; VI-NEXT: .amdhsa_exception_fp_ieee_invalid_op 0
; VI-NEXT: .amdhsa_exception_fp_denorm_src 0
; VI-NEXT: .amdhsa_exception_fp_ieee_div_zero 0
; VI-NEXT: .amdhsa_exception_fp_ieee_overflow 0
; VI-NEXT: .amdhsa_exception_fp_ieee_underflow 0
; VI-NEXT: .amdhsa_exception_fp_ieee_inexact 0
; VI-NEXT: .amdhsa_exception_int_div_zero 0
; VI-NEXT: .end_amdhsa_kernel
; VI-NEXT: .text
;
; GFX9-LABEL: alignstack_attr:
; GFX9: ; %bb.0:
; GFX9-NEXT: s_add_u32 s0, s0, s17
; GFX9-NEXT: s_addc_u32 s1, s1, 0
; GFX9-NEXT: v_mov_b32_e32 v0, 3
; GFX9-NEXT: buffer_store_byte v0, off, s[0:3], 0
; GFX9-NEXT: s_waitcnt vmcnt(0)
; GFX9-NEXT: v_mov_b32_e32 v0, 9
; GFX9-NEXT: buffer_store_dword v0, off, s[0:3], 0 offset:4
; GFX9-NEXT: s_waitcnt vmcnt(0)
; GFX9-NEXT: s_endpgm
; GFX9-NEXT: .section .rodata,"a"
; GFX9-NEXT: .p2align 6
; GFX9-NEXT: .amdhsa_kernel alignstack_attr
; GFX9-NEXT: .amdhsa_group_segment_fixed_size 0
; GFX9-NEXT: .amdhsa_private_segment_fixed_size 128
; GFX9-NEXT: .amdhsa_kernarg_size 56
; GFX9-NEXT: .amdhsa_user_sgpr_count 14
; GFX9-NEXT: .amdhsa_user_sgpr_private_segment_buffer 1
; GFX9-NEXT: .amdhsa_user_sgpr_dispatch_ptr 1
; GFX9-NEXT: .amdhsa_user_sgpr_queue_ptr 1
; GFX9-NEXT: .amdhsa_user_sgpr_kernarg_segment_ptr 1
; GFX9-NEXT: .amdhsa_user_sgpr_dispatch_id 1
; GFX9-NEXT: .amdhsa_user_sgpr_flat_scratch_init 1
; GFX9-NEXT: .amdhsa_user_sgpr_private_segment_size 0
; GFX9-NEXT: .amdhsa_system_sgpr_private_segment_wavefront_offset 1
; GFX9-NEXT: .amdhsa_system_sgpr_workgroup_id_x 1
; GFX9-NEXT: .amdhsa_system_sgpr_workgroup_id_y 1
; GFX9-NEXT: .amdhsa_system_sgpr_workgroup_id_z 1
; GFX9-NEXT: .amdhsa_system_sgpr_workgroup_info 0
; GFX9-NEXT: .amdhsa_system_vgpr_workitem_id 2
; GFX9-NEXT: .amdhsa_next_free_vgpr 3
; GFX9-NEXT: .amdhsa_next_free_sgpr 18
; GFX9-NEXT: .amdhsa_reserve_vcc 0
; GFX9-NEXT: .amdhsa_reserve_flat_scratch 0
; GFX9-NEXT: .amdhsa_reserve_xnack_mask 1
; GFX9-NEXT: .amdhsa_float_round_mode_32 0
; GFX9-NEXT: .amdhsa_float_round_mode_16_64 0
; GFX9-NEXT: .amdhsa_float_denorm_mode_32 3
; GFX9-NEXT: .amdhsa_float_denorm_mode_16_64 3
; GFX9-NEXT: .amdhsa_dx10_clamp 1
; GFX9-NEXT: .amdhsa_ieee_mode 1
; GFX9-NEXT: .amdhsa_fp16_overflow 0
; GFX9-NEXT: .amdhsa_exception_fp_ieee_invalid_op 0
; GFX9-NEXT: .amdhsa_exception_fp_denorm_src 0
; GFX9-NEXT: .amdhsa_exception_fp_ieee_div_zero 0
; GFX9-NEXT: .amdhsa_exception_fp_ieee_overflow 0
; GFX9-NEXT: .amdhsa_exception_fp_ieee_underflow 0
; GFX9-NEXT: .amdhsa_exception_fp_ieee_inexact 0
; GFX9-NEXT: .amdhsa_exception_int_div_zero 0
; GFX9-NEXT: .end_amdhsa_kernel
; GFX9-NEXT: .text
%clutter = alloca i8, addrspace(5) ; Force non-zero offset for next alloca
store volatile i8 3, ptr addrspace(5) %clutter
%alloca.align = alloca i32, align 4, addrspace(5)
store volatile i32 9, ptr addrspace(5) %alloca.align, align 4
ret void
}
attributes #0 = { nounwind }
attributes #1 = { nounwind "stackrealign" }
attributes #2 = { nounwind alignstack=128 }
!llvm.module.flags = !{!0}
!0 = !{i32 1, !"amdhsa_code_object_version", i32 400}