[llvm] r317750 - AMDGPU: Fold immediate offset into BUFFER_LOAD_DWORD lowered from SMEM
Marek Olsak via llvm-commits
llvm-commits at lists.llvm.org
Wed Nov 8 17:52:17 PST 2017
Author: mareko
Date: Wed Nov 8 17:52:17 2017
New Revision: 317750
URL: http://llvm.org/viewvc/llvm-project?rev=317750&view=rev
Log:
AMDGPU: Fold immediate offset into BUFFER_LOAD_DWORD lowered from SMEM
Summary:
-5.3% code size in affected shaders.
Changed stats only:
48486 shaders in 30489 tests
Totals:
SGPRS: 2086406 -> 2072430 (-0.67 %)
VGPRS: 1626872 -> 1627960 (0.07 %)
Spilled SGPRs: 7865 -> 7912 (0.60 %)
Code Size: 60978060 -> 60188764 (-1.29 %) bytes
Max Waves: 374530 -> 374342 (-0.05 %)
Totals from affected shaders:
SGPRS: 299664 -> 285688 (-4.66 %)
VGPRS: 233844 -> 234932 (0.47 %)
Spilled SGPRs: 3959 -> 4006 (1.19 %)
Code Size: 14905272 -> 14115976 (-5.30 %) bytes
Max Waves: 46202 -> 46014 (-0.41 %)
Reviewers: arsenm, nhaehnle
Subscribers: kzhuravl, wdng, yaxunl, dstuttard, tpr, llvm-commits, t-tye
Differential Revision: https://reviews.llvm.org/D38915
Modified:
llvm/trunk/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp
llvm/trunk/lib/Target/AMDGPU/SIInstrInfo.cpp
llvm/trunk/lib/Target/AMDGPU/SIInstrInfo.h
llvm/trunk/test/CodeGen/AMDGPU/smrd.ll
Modified: llvm/trunk/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp?rev=317750&r1=317749&r2=317750&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp (original)
+++ llvm/trunk/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp Wed Nov 8 17:52:17 2017
@@ -983,14 +983,6 @@ bool AMDGPUDAGToDAGISel::SelectDS64Bit4B
return true;
}
-static bool isLegalMUBUFImmOffset(unsigned Imm) {
- return isUInt<12>(Imm);
-}
-
-static bool isLegalMUBUFImmOffset(const ConstantSDNode *Imm) {
- return isLegalMUBUFImmOffset(Imm->getZExtValue());
-}
-
bool AMDGPUDAGToDAGISel::SelectMUBUF(SDValue Addr, SDValue &Ptr,
SDValue &VAddr, SDValue &SOffset,
SDValue &Offset, SDValue &Offen,
@@ -1032,7 +1024,7 @@ bool AMDGPUDAGToDAGISel::SelectMUBUF(SDV
Ptr = N0;
}
- if (isLegalMUBUFImmOffset(C1)) {
+ if (SIInstrInfo::isLegalMUBUFImmOffset(C1->getZExtValue())) {
Offset = CurDAG->getTargetConstant(C1->getZExtValue(), DL, MVT::i16);
return true;
}
@@ -1142,7 +1134,7 @@ bool AMDGPUDAGToDAGISel::SelectMUBUFScra
if (ConstantSDNode *CAddr = dyn_cast<ConstantSDNode>(Addr)) {
unsigned Imm = CAddr->getZExtValue();
- assert(!isLegalMUBUFImmOffset(Imm) &&
+ assert(!SIInstrInfo::isLegalMUBUFImmOffset(Imm) &&
"should have been selected by other pattern");
SDValue HighBits = CurDAG->getTargetConstant(Imm & ~4095, DL, MVT::i32);
@@ -1169,7 +1161,7 @@ bool AMDGPUDAGToDAGISel::SelectMUBUFScra
// Offsets in vaddr must be positive.
ConstantSDNode *C1 = cast<ConstantSDNode>(N1);
- if (isLegalMUBUFImmOffset(C1)) {
+ if (SIInstrInfo::isLegalMUBUFImmOffset(C1->getZExtValue())) {
std::tie(VAddr, SOffset) = foldFrameIndex(N0);
ImmOffset = CurDAG->getTargetConstant(C1->getZExtValue(), DL, MVT::i16);
return true;
@@ -1188,7 +1180,7 @@ bool AMDGPUDAGToDAGISel::SelectMUBUFScra
SDValue &SOffset,
SDValue &Offset) const {
ConstantSDNode *CAddr = dyn_cast<ConstantSDNode>(Addr);
- if (!CAddr || !isLegalMUBUFImmOffset(CAddr))
+ if (!CAddr || !SIInstrInfo::isLegalMUBUFImmOffset(CAddr->getZExtValue()))
return false;
SDLoc DL(Addr);
Modified: llvm/trunk/lib/Target/AMDGPU/SIInstrInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AMDGPU/SIInstrInfo.cpp?rev=317750&r1=317749&r2=317750&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AMDGPU/SIInstrInfo.cpp (original)
+++ llvm/trunk/lib/Target/AMDGPU/SIInstrInfo.cpp Wed Nov 8 17:52:17 2017
@@ -3712,13 +3712,43 @@ void SIInstrInfo::moveToVALU(MachineInst
case AMDGPU::S_BUFFER_LOAD_DWORD_SGPR: {
unsigned VDst = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
+ const MachineOperand *VAddr = getNamedOperand(Inst, AMDGPU::OpName::soff);
+ auto Add = MRI.getUniqueVRegDef(VAddr->getReg());
+ unsigned Offset = 0;
+
+ // See if we can extract an immediate offset by recognizing one of these:
+ // V_ADD_I32_e32 dst, imm, src1
+ // V_ADD_I32_e32 dst, (S_MOV_B32 imm), src1
+ // V_ADD will be removed by "Remove dead machine instructions".
+ if (Add && Add->getOpcode() == AMDGPU::V_ADD_I32_e32) {
+ const MachineOperand *Src =
+ getNamedOperand(*Add, AMDGPU::OpName::src0);
+
+ if (Src && Src->isReg()) {
+ auto Mov = MRI.getUniqueVRegDef(Src->getReg());
+ if (Mov && Mov->getOpcode() == AMDGPU::S_MOV_B32)
+ Src = &Mov->getOperand(1);
+ }
+
+ if (Src) {
+ if (Src->isImm())
+ Offset = Src->getImm();
+ else if (Src->isCImm())
+ Offset = Src->getCImm()->getZExtValue();
+ }
+
+ if (Offset && isLegalMUBUFImmOffset(Offset))
+ VAddr = getNamedOperand(*Add, AMDGPU::OpName::src1);
+ else
+ Offset = 0;
+ }
BuildMI(*MBB, Inst, Inst.getDebugLoc(),
get(AMDGPU::BUFFER_LOAD_DWORD_OFFEN), VDst)
- .add(*getNamedOperand(Inst, AMDGPU::OpName::soff)) // vaddr
+ .add(*VAddr) // vaddr
.add(*getNamedOperand(Inst, AMDGPU::OpName::sbase)) // srsrc
.addImm(0) // soffset
- .addImm(0) // offset
+ .addImm(Offset) // offset
.addImm(getNamedOperand(Inst, AMDGPU::OpName::glc)->getImm())
.addImm(0) // slc
.addImm(0) // tfe
Modified: llvm/trunk/lib/Target/AMDGPU/SIInstrInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AMDGPU/SIInstrInfo.h?rev=317750&r1=317749&r2=317750&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AMDGPU/SIInstrInfo.h (original)
+++ llvm/trunk/lib/Target/AMDGPU/SIInstrInfo.h Wed Nov 8 17:52:17 2017
@@ -860,6 +860,10 @@ public:
static bool isKillTerminator(unsigned Opcode);
const MCInstrDesc &getKillTerminatorFromPseudo(unsigned Opcode) const;
+
+ static bool isLegalMUBUFImmOffset(unsigned Imm) {
+ return isUInt<12>(Imm);
+ }
};
namespace AMDGPU {
Modified: llvm/trunk/test/CodeGen/AMDGPU/smrd.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/AMDGPU/smrd.ll?rev=317750&r1=317749&r2=317750&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/AMDGPU/smrd.ll (original)
+++ llvm/trunk/test/CodeGen/AMDGPU/smrd.ll Wed Nov 8 17:52:17 2017
@@ -191,6 +191,27 @@ main_body:
ret float %r
}
+; GCN-LABEL: {{^}}smrd_vgpr_offset_imm:
+; GCN-NEXT: BB#
+; GCN-NEXT: buffer_load_dword v{{[0-9]}}, v0, s[0:3], 0 offen offset:4095 ;
+define amdgpu_ps float @smrd_vgpr_offset_imm(<4 x i32> inreg %desc, i32 %offset) #0 {
+main_body:
+ %off = add i32 %offset, 4095
+ %r = call float @llvm.SI.load.const.v4i32(<4 x i32> %desc, i32 %off)
+ ret float %r
+}
+
+; GCN-LABEL: {{^}}smrd_vgpr_offset_imm_too_large:
+; GCN-NEXT: BB#
+; GCN-NEXT: v_add_i32_e32 v0, vcc, 0x1000, v0
+; GCN-NEXT: buffer_load_dword v{{[0-9]}}, v0, s[0:3], 0 offen ;
+define amdgpu_ps float @smrd_vgpr_offset_imm_too_large(<4 x i32> inreg %desc, i32 %offset) #0 {
+main_body:
+ %off = add i32 %offset, 4096
+ %r = call float @llvm.SI.load.const.v4i32(<4 x i32> %desc, i32 %off)
+ ret float %r
+}
+
declare void @llvm.amdgcn.exp.f32(i32, i32, float, float, float, float, i1, i1) #0
declare float @llvm.SI.load.const.v4i32(<4 x i32>, i32) #1
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