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[AMDGPU] Remove subtarget features for dynamic VGPRs #160822

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merged 3 commits into from
Oct 6, 2025
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[AMDGPU] Remove subtarget features for dynamic VGPRs #160822

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82d978a
[AMDGPU] Remove subtarget features for dynamic VGPRs
rovka Sep 25, 2025
b8375c5
Merge branch 'main' into users/rovka/remove-dvgpr-target-features
rovka Sep 26, 2025
57f50ad
Merge branch 'main' into users/rovka/remove-dvgpr-target-features
rovka Oct 1, 2025
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14 changes: 0 additions & 14 deletions llvm/lib/Target/AMDGPU/AMDGPU.td
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Original file line number Diff line number Diff line change
Expand Up @@ -1411,20 +1411,6 @@ def FeatureGloballyAddressableScratch : SubtargetFeature<
"FLAT instructions can access scratch memory for any thread in any wave"
>;

// FIXME: Remove after all users are migrated to attribute.
def FeatureDynamicVGPR : SubtargetFeature <"dynamic-vgpr",
"DynamicVGPR",
"true",
"Enable dynamic VGPR mode"
>;

// FIXME: Remove after all users are migrated to attribute.
def FeatureDynamicVGPRBlockSize32 : SubtargetFeature<"dynamic-vgpr-block-size-32",
"DynamicVGPRBlockSize32",
"true",
"Use a block size of 32 for dynamic VGPR allocation (default is 16)"
>;

// Enable the use of SCRATCH_STORE/LOAD_BLOCK instructions for saving and
// restoring the callee-saved registers.
def FeatureUseBlockVGPROpsForCSR : SubtargetFeature<"block-vgpr-csr",
Expand Down
10 changes: 1 addition & 9 deletions llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1353,11 +1353,6 @@ unsigned getVGPRAllocGranule(const MCSubtargetInfo *STI,
if (DynamicVGPRBlockSize != 0)
return DynamicVGPRBlockSize;

// Temporarily check the subtarget feature, until we fully switch to using
// attributes.
if (STI->getFeatureBits().test(FeatureDynamicVGPR))
return STI->getFeatureBits().test(FeatureDynamicVGPRBlockSize32) ? 32 : 16;

bool IsWave32 = EnableWavefrontSize32
? *EnableWavefrontSize32
: STI->getFeatureBits().test(FeatureWavefrontSize32);
Expand Down Expand Up @@ -1412,10 +1407,7 @@ unsigned getAddressableNumVGPRs(const MCSubtargetInfo *STI,
if (Features.test(FeatureGFX90AInsts))
return 512;

// Temporarily check the subtarget feature, until we fully switch to using
// attributes.
if (DynamicVGPRBlockSize != 0 ||
STI->getFeatureBits().test(FeatureDynamicVGPR))
if (DynamicVGPRBlockSize != 0)
// On GFX12 we can allocate at most 8 blocks of VGPRs.
return 8 * getVGPRAllocGranule(STI, DynamicVGPRBlockSize);
return getAddressableNumArchVGPRs(STI);
Expand Down
2 changes: 0 additions & 2 deletions llvm/test/CodeGen/AMDGPU/pal-metadata-3.0-callable.ll
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Original file line number Diff line number Diff line change
@@ -1,13 +1,11 @@
; RUN: llc -mtriple=amdgcn--amdpal -mcpu=gfx1100 < %s | FileCheck --check-prefixes=CHECK,GFX11 %s
; RUN: llc -mtriple=amdgcn--amdpal -mcpu=gfx1200 < %s | FileCheck --check-prefixes=CHECK,GFX12 %s
; RUN: llc -mtriple=amdgcn--amdpal -mcpu=gfx1200 -mattr=+dynamic-vgpr < %s | FileCheck --check-prefixes=CHECK,GFX12,DVGPR %s

; CHECK: .amdgpu_pal_metadata
; CHECK-NEXT: ---
; CHECK-NEXT: amdpal.pipelines:
; CHECK-NEXT: - .api: Vulkan
; CHECK-NEXT: .compute_registers:
; DVGPR-NEXT: .dynamic_vgpr_en: true
; CHECK-NEXT: .tg_size_en: true
; CHECK-NEXT: .tgid_x_en: false
; CHECK-NEXT: .tgid_y_en: false
Expand Down
13 changes: 4 additions & 9 deletions llvm/test/CodeGen/AMDGPU/pal-metadata-3.0.ll
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Original file line number Diff line number Diff line change
@@ -1,17 +1,14 @@
; RUN: llc -mtriple=amdgcn--amdpal -mcpu=gfx1100 <%s | FileCheck %s --check-prefixes=CHECK,GFX11,NODVGPR
; RUN: llc -mtriple=amdgcn--amdpal -mcpu=gfx1200 <%s | FileCheck %s --check-prefixes=CHECK,NODVGPR
; RUN: llc -mtriple=amdgcn--amdpal -mcpu=gfx1200 -mattr=+dynamic-vgpr <%s | FileCheck %s --check-prefixes=CHECK,DVGPR
; RUN: llc -mtriple=amdgcn--amdpal -mcpu=gfx1100 <%s | FileCheck %s --check-prefixes=CHECK,GFX11
; RUN: llc -mtriple=amdgcn--amdpal -mcpu=gfx1200 <%s | FileCheck %s --check-prefixes=CHECK

; CHECK-LABEL: {{^}}_amdgpu_cs_main:
; NODVGPR: ; TotalNumSgprs: 4
; DVGPR: ; TotalNumSgprs: 34
; CHECK: ; TotalNumSgprs: 4
; CHECK: ; NumVgprs: 2
; CHECK: .amdgpu_pal_metadata
; CHECK-NEXT: ---
; CHECK-NEXT: amdpal.pipelines:
; CHECK-NEXT: - .api: Vulkan
; CHECK-NEXT: .compute_registers:
; DVGPR-NEXT: .dynamic_vgpr_en: true
; CHECK-NEXT: .tg_size_en: true
; CHECK-NEXT: .tgid_x_en: false
; CHECK-NEXT: .tgid_y_en: false
Expand Down Expand Up @@ -57,7 +54,6 @@
; CHECK-NEXT: .cs:
; CHECK-NEXT: .checksum_value: 0x9444d7d0
; CHECK-NEXT: .debug_mode: false
; DVGPR-NEXT: .dynamic_vgpr_saved_count: 0x70
; CHECK-NEXT: .entry_point: _amdgpu_cs_main
; CHECK-NEXT: .entry_point_symbol: _amdgpu_cs_main
; CHECK-NEXT: .excp_en: 0
Expand All @@ -69,8 +65,7 @@
; CHECK-NEXT: .mem_ordered: true
; CHECK-NEXT: .scratch_en: false
; CHECK-NEXT: .scratch_memory_size: 0
; NODVGPR-NEXT: .sgpr_count: 0x4
; DVGPR-NEXT: .sgpr_count: 0x22
; CHECK-NEXT: .sgpr_count: 0x4
; CHECK-NEXT: .sgpr_limit: 0x6a
; CHECK-NEXT: .threadgroup_dimensions:
; CHECK-NEXT: - 0x1
Expand Down
204 changes: 204 additions & 0 deletions llvm/test/CodeGen/AMDGPU/pal-metadata-3.6-dvgpr.ll
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Original file line number Diff line number Diff line change
@@ -0,0 +1,204 @@
; RUN: llc -mtriple=amdgcn--amdpal -mcpu=gfx1200 <%s | FileCheck %s --check-prefixes=CHECK

; CHECK-LABEL: {{^}}_amdgpu_cs_main:
; CHECK: ; TotalNumSgprs: 34
; CHECK: ; NumVgprs: 2
; CHECK: .amdgpu_pal_metadata
; CHECK-NEXT: ---
; CHECK-NEXT: amdpal.pipelines:
; CHECK-NEXT: - .api: Vulkan
; CHECK-NEXT: .compute_registers:
; CHECK-NEXT: .dynamic_vgpr_en: true
; CHECK-NEXT: .tg_size_en: true
; CHECK-NEXT: .tgid_x_en: false
; CHECK-NEXT: .tgid_y_en: false
; CHECK-NEXT: .tgid_z_en: false
; CHECK-NEXT: .tidig_comp_cnt: 0x1
; CHECK-NEXT: .graphics_registers:
; CHECK-NEXT: .ps_extra_lds_size: 0
; CHECK-NEXT: .spi_ps_input_addr:
; CHECK-NEXT: .ancillary_ena: false
; CHECK-NEXT: .front_face_ena: true
; CHECK-NEXT: .line_stipple_tex_ena: false
; CHECK-NEXT: .linear_center_ena: true
; CHECK-NEXT: .linear_centroid_ena: true
; CHECK-NEXT: .linear_sample_ena: true
; CHECK-NEXT: .persp_center_ena: true
; CHECK-NEXT: .persp_centroid_ena: true
; CHECK-NEXT: .persp_pull_model_ena: false
; CHECK-NEXT: .persp_sample_ena: true
; CHECK-NEXT: .pos_fixed_pt_ena: true
; CHECK-NEXT: .pos_w_float_ena: false
; CHECK-NEXT: .pos_x_float_ena: false
; CHECK-NEXT: .pos_y_float_ena: false
; CHECK-NEXT: .pos_z_float_ena: false
; CHECK-NEXT: .sample_coverage_ena: false
; CHECK-NEXT: .spi_ps_input_ena:
; CHECK-NEXT: .ancillary_ena: false
; CHECK-NEXT: .front_face_ena: false
; CHECK-NEXT: .line_stipple_tex_ena: false
; CHECK-NEXT: .linear_center_ena: false
; CHECK-NEXT: .linear_centroid_ena: false
; CHECK-NEXT: .linear_sample_ena: false
; CHECK-NEXT: .persp_center_ena: false
; CHECK-NEXT: .persp_centroid_ena: false
; CHECK-NEXT: .persp_pull_model_ena: false
; CHECK-NEXT: .persp_sample_ena: true
; CHECK-NEXT: .pos_fixed_pt_ena: false
; CHECK-NEXT: .pos_w_float_ena: false
; CHECK-NEXT: .pos_x_float_ena: false
; CHECK-NEXT: .pos_y_float_ena: false
; CHECK-NEXT: .pos_z_float_ena: false
; CHECK-NEXT: .sample_coverage_ena: false
; CHECK-NEXT: .hardware_stages:
; CHECK-NEXT: .cs:
; CHECK-NEXT: .checksum_value: 0x9444d7d0
; CHECK-NEXT: .debug_mode: false
; CHECK-NEXT: .dynamic_vgpr_saved_count: 0x70
; CHECK-NOT: .entry_point: _amdgpu_cs_main
; CHECK-NEXT: .entry_point_symbol: _amdgpu_cs_main
; CHECK-NEXT: .excp_en: 0
; CHECK-NEXT: .float_mode: 0xc0
; CHECK-NEXT: .forward_progress: true
; GFX11-NEXT: .ieee_mode: false
; CHECK-NEXT: .image_op: false
; CHECK-NEXT: .lds_size: 0
; CHECK-NEXT: .mem_ordered: true
; CHECK-NEXT: .scratch_en: false
; CHECK-NEXT: .scratch_memory_size: 0
; CHECK-NEXT: .sgpr_count: 0x22
; CHECK-NEXT: .sgpr_limit: 0x6a
; CHECK-NEXT: .threadgroup_dimensions:
; CHECK-NEXT: - 0x1
; CHECK-NEXT: - 0x400
; CHECK-NEXT: - 0x1
; CHECK-NEXT: .trap_present: false
; CHECK-NEXT: .user_data_reg_map:
; CHECK-NEXT: - 0x10000000
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: - 0xffffffff
; CHECK-NEXT: .user_sgprs: 0x3
; CHECK-NEXT: .vgpr_count: 0x2
; CHECK-NEXT: .vgpr_limit: 0x100
; CHECK-NEXT: .wavefront_size: 0x40
; CHECK-NEXT: .wgp_mode: false
; CHECK-NEXT: .gs:
; CHECK-NEXT: .debug_mode: false
; CHECK-NOT: .entry_point: _amdgpu_gs_main
; CHECK-NEXT: .entry_point_symbol: gs_shader
; CHECK-NEXT: .forward_progress: true
; GFX11-NEXT: .ieee_mode: false
; CHECK-NEXT: .lds_size: 0x200
; CHECK-NEXT: .mem_ordered: true
; CHECK-NEXT: .scratch_en: false
; CHECK-NEXT: .scratch_memory_size: 0
; CHECK-NEXT: .sgpr_count: 0x1
; CHECK-NEXT: .vgpr_count: 0x1
; CHECK-NEXT: .wgp_mode: true
; CHECK-NEXT: .hs:
; CHECK-NEXT: .debug_mode: false
; CHECK-NOT: .entry_point: _amdgpu_hs_main
; CHECK-NEXT: .entry_point_symbol: hs_shader
; CHECK-NEXT: .forward_progress: true
; GFX11-NEXT: .ieee_mode: false
; CHECK-NEXT: .lds_size: 0x1000
; CHECK-NEXT: .mem_ordered: true
; CHECK-NEXT: .scratch_en: false
; CHECK-NEXT: .scratch_memory_size: 0
; CHECK-NEXT: .sgpr_count: 0x1
; CHECK-NEXT: .vgpr_count: 0x1
; CHECK-NEXT: .wgp_mode: true
; CHECK-NEXT: .ps:
; CHECK-NEXT: .debug_mode: false
; CHECK-NOT: .entry_point: _amdgpu_ps_main
; CHECK-NEXT: .entry_point_symbol: ps_shader
; CHECK-NEXT: .forward_progress: true
; GFX11-NEXT: .ieee_mode: false
; CHECK-NEXT: .lds_size: 0
; CHECK-NEXT: .mem_ordered: true
; CHECK-NEXT: .scratch_en: false
; CHECK-NEXT: .scratch_memory_size: 0
; CHECK-NEXT: .sgpr_count: 0x1
; CHECK-NEXT: .vgpr_count: 0x1
; CHECK-NEXT: .wgp_mode: true
; CHECK: .registers: {}
; CHECK:amdpal.version:
; CHECK-NEXT: - 0x3
; CHECK-NEXT: - 0x6
; CHECK-NEXT:...
; CHECK-NEXT: .end_amdgpu_pal_metadata

define dllexport amdgpu_cs void @_amdgpu_cs_main(i32 inreg %arg1, i32 %arg2) #0 !lgc.shaderstage !1 {
.entry:
%i = call i64 @llvm.amdgcn.s.getpc()
%i1 = and i64 %i, -4294967296
%i2 = zext i32 %arg1 to i64
%i3 = or i64 %i1, %i2
%i4 = inttoptr i64 %i3 to ptr addrspace(4)
%i5 = and i32 %arg2, 1023
%i6 = lshr i32 %arg2, 10
%i7 = and i32 %i6, 1023
%i8 = add nuw nsw i32 %i7, %i5
%i9 = load <4 x i32>, ptr addrspace(4) %i4, align 16
%.idx = shl nuw nsw i32 %i8, 2
call void @llvm.amdgcn.raw.buffer.store.i32(i32 1, <4 x i32> %i9, i32 %.idx, i32 0, i32 0)
ret void
}

define dllexport amdgpu_ps void @ps_shader() #1 {
ret void
}

@LDS.GS = external addrspace(3) global [1 x i32], align 4

define dllexport amdgpu_gs void @gs_shader() {
%ptr = getelementptr i32, ptr addrspace(3) @LDS.GS, i32 0
store i32 0, ptr addrspace(3) %ptr, align 4
ret void
}

@LDS.HS = external addrspace(3) global [1024 x i32], align 4

define dllexport amdgpu_hs void @hs_shader() {
%ptr = getelementptr i32, ptr addrspace(3) @LDS.HS, i32 0
store i32 0, ptr addrspace(3) %ptr, align 4
ret void
}

!amdgpu.pal.metadata.msgpack = !{!0}

attributes #0 = { nounwind memory(readwrite) "target-features"=",+wavefrontsize64,+cumode" "amdgpu-dynamic-vgpr-block-size"="16" }

attributes #1 = { nounwind memory(readwrite) "InitialPSInputAddr"="36983" "amdgpu-dynamic-vgpr-block-size"="16" }

!0 = !{!"\82\B0amdpal.pipelines\91\8A\A4.api\A6Vulkan\B2.compute_registers\85\AB.tg_size_en\C3\AA.tgid_x_en\C2\AA.tgid_y_en\C2\AA.tgid_z_en\C2\AF.tidig_comp_cnt\01\B0.hardware_stages\81\A3.cs\8C\AF.checksum_value\CE\94D\D7\D0\AB.debug_mode\00\AB.float_mode\CC\C0\A9.image_op\C2\AC.mem_ordered\C3\AB.sgpr_limitj\B7.threadgroup_dimensions\93\01\CD\04\00\01\AD.trap_present\00\B2.user_data_reg_map\DC\00 \CE\10\00\00\00\CE\FF\FF\FF\FF\00\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\CE\FF\FF\FF\FF\AB.user_sgprs\03\AB.vgpr_limit\CD\01\00\AF.wavefront_size@\B7.internal_pipeline_hash\92\CF\E7\10k\A6:\A6%\F7\CF\B2\1F\1A\D4{\DA\E1T\AA.registers\80\A8.shaders\81\A8.compute\82\B0.api_shader_hash\92\CF\E9Zn7}\1E\B9\E7\00\B1.hardware_mapping\91\A3.cs\B0.spill_threshold\CE\FF\FF\FF\FF\A5.type\A2Cs\B0.user_data_limit\01\AF.xgl_cache_info\82\B3.128_bit_cache_hash\92\CF\B4X\B8\11[\A4\88P\CF\A0;\B0\AF\FF\B4\BE\C0\AD.llpc_version\A461.1\AEamdpal.version\92\03\06"}
!1 = !{i32 7}
13 changes: 4 additions & 9 deletions llvm/test/CodeGen/AMDGPU/pal-metadata-3.6.ll
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Original file line number Diff line number Diff line change
@@ -1,17 +1,14 @@
; RUN: llc -mtriple=amdgcn--amdpal -mcpu=gfx1100 <%s | FileCheck %s --check-prefixes=CHECK,GFX11,NODVGPR
; RUN: llc -mtriple=amdgcn--amdpal -mcpu=gfx1200 <%s | FileCheck %s --check-prefixes=CHECK,NODVGPR
; RUN: llc -mtriple=amdgcn--amdpal -mcpu=gfx1200 -mattr=+dynamic-vgpr <%s | FileCheck %s --check-prefixes=CHECK,DVGPR
; RUN: llc -mtriple=amdgcn--amdpal -mcpu=gfx1100 <%s | FileCheck %s --check-prefixes=CHECK,GFX11
; RUN: llc -mtriple=amdgcn--amdpal -mcpu=gfx1200 <%s | FileCheck %s --check-prefixes=CHECK

; CHECK-LABEL: {{^}}_amdgpu_cs_main:
; NODVGPR: ; TotalNumSgprs: 4
; DVGPR: ; TotalNumSgprs: 34
; CHECK: ; TotalNumSgprs: 4
; CHECK: ; NumVgprs: 2
; CHECK: .amdgpu_pal_metadata
; CHECK-NEXT: ---
; CHECK-NEXT: amdpal.pipelines:
; CHECK-NEXT: - .api: Vulkan
; CHECK-NEXT: .compute_registers:
; DVGPR-NEXT: .dynamic_vgpr_en: true
; CHECK-NEXT: .tg_size_en: true
; CHECK-NEXT: .tgid_x_en: false
; CHECK-NEXT: .tgid_y_en: false
Expand Down Expand Up @@ -57,7 +54,6 @@
; CHECK-NEXT: .cs:
; CHECK-NEXT: .checksum_value: 0x9444d7d0
; CHECK-NEXT: .debug_mode: false
; DVGPR-NEXT: .dynamic_vgpr_saved_count: 0x70
; CHECK-NOT: .entry_point: _amdgpu_cs_main
; CHECK-NEXT: .entry_point_symbol: _amdgpu_cs_main
; CHECK-NEXT: .excp_en: 0
Expand All @@ -69,8 +65,7 @@
; CHECK-NEXT: .mem_ordered: true
; CHECK-NEXT: .scratch_en: false
; CHECK-NEXT: .scratch_memory_size: 0
; NODVGPR-NEXT: .sgpr_count: 0x4
; DVGPR-NEXT: .sgpr_count: 0x22
; CHECK-NEXT: .sgpr_count: 0x4
; CHECK-NEXT: .sgpr_limit: 0x6a
; CHECK-NEXT: .threadgroup_dimensions:
; CHECK-NEXT: - 0x1
Expand Down