[AMDGPU] Preliminary patch for divergence driven instruction selection. Operands Folding 1.

Reviewers: rampitec

Differential revision: https://reviews/llvm/org/D51316

llvm-svn: 341068
This commit is contained in:
Alexander Timofeev 2018-08-30 13:55:04 +00:00
parent ca49e391b3
commit 201f892b3b
2 changed files with 47 additions and 2 deletions

View File

@ -438,8 +438,6 @@ void SIFoldOperands::foldOperand(
bool FoldingImm = OpToFold.isImm();
// In order to fold immediates into copies, we need to change the
// copy to a MOV.
if (FoldingImm && UseMI->isCopy()) {
unsigned DestReg = UseMI->getOperand(0).getReg();
const TargetRegisterClass *DestRC
@ -447,6 +445,31 @@ void SIFoldOperands::foldOperand(
MRI->getRegClass(DestReg) :
TRI->getPhysRegClass(DestReg);
unsigned SrcReg = UseMI->getOperand(1).getReg();
if (TargetRegisterInfo::isVirtualRegister(DestReg) &&
TargetRegisterInfo::isVirtualRegister(SrcReg)) {
const TargetRegisterClass * SrcRC = MRI->getRegClass(SrcReg);
if (TRI->isSGPRClass(SrcRC) && TRI->hasVGPRs(DestRC)) {
MachineRegisterInfo::use_iterator NextUse;
SmallVector<FoldCandidate, 4> CopyUses;
for (MachineRegisterInfo::use_iterator
Use = MRI->use_begin(DestReg), E = MRI->use_end();
Use != E; Use = NextUse) {
NextUse = std::next(Use);
FoldCandidate FC = FoldCandidate(Use->getParent(),
Use.getOperandNo(), &UseMI->getOperand(1));
CopyUses.push_back(FC);
}
for (auto & F : CopyUses) {
foldOperand(*F.OpToFold, F.UseMI, F.UseOpNo,
FoldList, CopiesToReplace);
}
}
}
// In order to fold immediates into copies, we need to change the
// copy to a MOV.
unsigned MovOp = TII->getMovOpcode(DestRC);
if (MovOp == AMDGPU::COPY)
return;

View File

@ -0,0 +1,22 @@
# RUN: llc -march=amdgcn -run-pass si-fold-operands %s -o - | FileCheck -check-prefix=GCN %s
# GCN-LABEL: name: fold-imm-copy
# GCN: [[SREG:%[0-9+]]]:sreg_32_xm0 = S_MOV_B32 65535
# GCN: V_AND_B32_e32 [[SREG]]
name: fold-imm-copy
body: |
bb.0:
liveins: $vgpr0, $sgpr0_sgpr1
%0:vgpr_32 = COPY $vgpr0
%1:sgpr_64 = COPY $sgpr0_sgpr1
%2:sreg_128 = S_LOAD_DWORDX4_IMM %1, 9, 0
%3:sreg_32_xm0 = S_MOV_B32 2
%4:vgpr_32 = V_LSHLREV_B32_e64 killed %3, %0, implicit $exec
%5:vgpr_32 = V_MOV_B32_e32 0, implicit $exec
%6:vreg_64 = REG_SEQUENCE killed %4, %subreg.sub0, killed %5, %subreg.sub1
%7:vgpr_32 = BUFFER_LOAD_DWORD_ADDR64 %6, %2, 0, 4, 0, 0, 0, implicit $exec
%8:sreg_32_xm0 = S_MOV_B32 65535
%9:vgpr_32 = COPY %8
%10:vgpr_32 = V_AND_B32_e32 %7, %9, implicit $exec
...