llvm-project/llvm/test/CodeGen/AMDGPU/llvm.amdgcn.tbuffer.store.d...

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; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=tonga -verify-machineinstrs < %s | FileCheck -enable-var-scope -check-prefix=GCN -check-prefix=UNPACKED %s
; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx810 -verify-machineinstrs < %s | FileCheck -enable-var-scope -check-prefix=GCN -check-prefix=PACKED -check-prefix=GFX81 %s
; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx900 -verify-machineinstrs < %s | FileCheck -enable-var-scope -check-prefix=GCN -check-prefix=PACKED -check-prefix=GFX9 %s
; GCN-LABEL: {{^}}tbuffer_store_d16_x:
AMDGPU: Try a lot harder to emit scalar loads This has two main components. First, widen widen short constant loads in DAG when they have the correct alignment. This is already done a bit in AMDGPUCodeGenPrepare, since that has access to DivergenceAnalysis. This can't help kernarg loads created in the DAG. Start to use DAG divergence analysis to help this case. The second part is to avoid kernel argument lowering breaking the alignment of short vector elements because calling convention lowering wants to split everything into legal register types. When loading a split type, load the nearest 4-byte aligned segment and shift to get the desired bits. This extra load of the earlier argument piece ends up merging, and the bit extract hopefully folds out. There are a number of improvements and regressions with this, but I think as-is this is a better compromise between several of the worst parts of SelectionDAG. Particularly when i16 is legal, this produces worse code for i8 and i16 element vector kernel arguments. This is partially due to the very weak load merging the DAG does. It only looks for fairly specific combines between pairs of loads which no longer appear. In particular this causes v4i16 loads to be split into 2 components when previously the two halves were merged. Worse, because of the newly introduced shifts, there is a lot more unnecessary vector packing and unpacking code emitted. At least some of this is due to reporting false for isTypeDesirableForOp for i16 as a workaround for the lack of divergence information in the DAG. The cases where this happens it doesn't actually matter, but the relevant code in SimplifyDemandedBits doens't have the context to know to ignore this. The use of the scalar cache is probably more important than the mess of mostly scalar instructions doing this packing and unpacking. Future work can fix this, possibly by making better use of the new DAG divergence information for controlling promotion decisions, or adding another version of shift + trunc + shift combines that doesn't only know about the used types. llvm-svn: 334180
2018-06-07 17:54:49 +08:00
; GCN: s_load_dword s[[S_LO:[0-9]+]]
; GCN: v_mov_b32_e32 v[[V_LO:[0-9]+]], s[[S_LO]]
; GCN: tbuffer_store_format_d16_x v[[V_LO]], v{{[0-9]+}}, s[{{[0-9]+:[0-9]+}}], dfmt:1, nfmt:2, 0 idxen
AMDGPU: Add pass to lower kernel arguments to loads This replaces most argument uses with loads, but for now not all. The code in SelectionDAG for calling convention lowering is actively harmful for amdgpu_kernel. It attempts to split the argument types into register legal types, which results in low quality code for arbitary types. Since all kernel arguments are passed in memory, we just want the raw types. I've tried a couple of methods of mitigating this in SelectionDAG, but it's easier to just bypass this problem alltogether. It's possible to hack around the problem in the initial lowering, but the real problem is the DAG then expects to be able to use CopyToReg/CopyFromReg for uses of the arguments outside the block. Exposing the argument loads in the IR also has the advantage that the LoadStoreVectorizer can merge them. I'm not sure the best approach to dealing with the IR argument list is. The patch as-is just leaves the IR arguments in place, so all the existing code will still compute the same kernarg size and pointlessly lowers the arguments. Arguably the frontend should emit kernels with an empty argument list in the first place. Alternatively a dummy array could be inserted as a single argument just to reserve space. This does have some disadvantages. Local pointer kernel arguments can no longer have AssertZext placed on them as the equivalent !range metadata is not valid on pointer typed loads. This is mostly bad for SI which needs to know about the known bits in order to use the DS instruction offset, so in this case this is not done. More importantly, this skips noalias arguments since this pass does not yet convert this to the equivalent !alias.scope and !noalias metadata. Producing this metadata correctly seems to be tricky, although this logically is the same as inlining into a function which doesn't exist. Additionally, exposing these loads to the vectorizer may result in degraded aliasing information if a pointer load is merged with another argument load. I'm also not entirely sure this is preserving the current clover ABI, although I would greatly prefer if it would stop widening arguments and match the HSA ABI. As-is I think it is extending < 4-byte arguments to 4-bytes but doesn't align them to 4-bytes. llvm-svn: 335650
2018-06-27 03:10:00 +08:00
define amdgpu_kernel void @tbuffer_store_d16_x(<4 x i32> %rsrc, [8 x i32], half %data, [8 x i32], i32 %vindex) {
main_body:
call void @llvm.amdgcn.tbuffer.store.f16(half %data, <4 x i32> %rsrc, i32 %vindex, i32 0, i32 0, i32 0, i32 1, i32 2, i1 0, i1 0)
ret void
}
; GCN-LABEL: {{^}}tbuffer_store_d16_xy:
; GCN: s_load_dword [[S_DATA:s[0-9]+]], s{{\[[0-9]+:[0-9]+\]}}, 0x10
; UNPACKED-DAG: s_lshr_b32 [[SHR:s[0-9]+]], [[S_DATA]], 16
; UNPACKED-DAG: s_and_b32 [[MASKED:s[0-9]+]], [[S_DATA]], 0xffff{{$}}
; UNPACKED-DAG: v_mov_b32_e32 v[[V_LO:[0-9]+]], [[MASKED]]
; UNPACKED-DAG: v_mov_b32_e32 v[[V_HI:[0-9]+]], [[SHR]]
; UNPACKED: tbuffer_store_format_d16_xy v{{\[}}[[V_LO]]:[[V_HI]]{{\]}}, v{{[0-9]+}}, s[{{[0-9]+:[0-9]+}}], dfmt:1, nfmt:2, 0 idxen
; PACKED: tbuffer_store_format_d16_xy v{{[0-9]+}}, v{{[0-9]+}}, s[{{[0-9]+:[0-9]+}}], dfmt:1, nfmt:2, 0 idxen
define amdgpu_kernel void @tbuffer_store_d16_xy(<4 x i32> %rsrc, <2 x half> %data, i32 %vindex) {
main_body:
call void @llvm.amdgcn.tbuffer.store.v2f16(<2 x half> %data, <4 x i32> %rsrc, i32 %vindex, i32 0, i32 0, i32 0, i32 1, i32 2, i1 0, i1 0)
ret void
}
; GCN-LABEL: {{^}}tbuffer_store_d16_xyzw:
; GCN-DAG: s_load_dwordx2 s{{\[}}[[S_DATA_0:[0-9]+]]:[[S_DATA_1:[0-9]+]]{{\]}}, s{{\[[0-9]+:[0-9]+\]}}, 0x10
; UNPACKED-DAG: s_mov_b32 [[K:s[0-9]+]], 0xffff{{$}}
; UNPACKED-DAG: s_lshr_b32 [[SHR0:s[0-9]+]], s[[S_DATA_0]], 16
; UNPACKED-DAG: s_and_b32 [[MASKED0:s[0-9]+]], s[[S_DATA_0]], [[K]]
; UNPACKED-DAG: s_lshr_b32 [[SHR1:s[0-9]+]], s[[S_DATA_1]], 16
; UNPACKED-DAG: s_and_b32 [[MASKED1:s[0-9]+]], s[[S_DATA_1]], [[K]]
; UNPACKED-DAG: v_mov_b32_e32 v[[LO:[0-9]+]], [[MASKED0]]
; UNPACKED-DAG: v_mov_b32_e32 v[[HI:[0-9]+]], [[SHR1]]
; UNPACKED: tbuffer_store_format_d16_xyzw v{{\[}}[[LO]]:[[HI]]{{\]}}, v{{[0-9]+}}, s[{{[0-9]+:[0-9]+}}], dfmt:1, nfmt:2, 0 idxen
; PACKED-DAG: v_mov_b32_e32 v[[LO:[0-9]+]], s[[S_DATA_0]]
; PACKED-DAG: v_mov_b32_e32 v[[HI:[0-9]+]], s[[S_DATA_1]]
; PACKED: tbuffer_store_format_d16_xyzw v{{\[}}[[LO]]:[[HI]]{{\]}}, v{{[0-9]+}}, s[{{[0-9]+:[0-9]+}}], dfmt:1, nfmt:2, 0 idxen
define amdgpu_kernel void @tbuffer_store_d16_xyzw(<4 x i32> %rsrc, <4 x half> %data, i32 %vindex) {
main_body:
call void @llvm.amdgcn.tbuffer.store.v4f16(<4 x half> %data, <4 x i32> %rsrc, i32 %vindex, i32 0, i32 0, i32 0, i32 1, i32 2, i1 0, i1 0)
ret void
}
declare void @llvm.amdgcn.tbuffer.store.f16(half, <4 x i32>, i32, i32, i32, i32, i32, i32, i1, i1)
declare void @llvm.amdgcn.tbuffer.store.v2f16(<2 x half>, <4 x i32>, i32, i32, i32, i32, i32, i32, i1, i1)
declare void @llvm.amdgcn.tbuffer.store.v4f16(<4 x half>, <4 x i32>, i32, i32, i32, i32, i32, i32, i1, i1)