maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

[Statepoints] Allow deopt GC pointer on VReg if gc-live bundle is empty. 

Currently we allow passing pointers from deopt bundle on VReg only if
they were seen in list of gc-live pointers passed on VRegs.
This means that for the case of empty gc-live bundle we spill deopt
bundle's pointers. This change allows lowering deopt pointers to VRegs
in case of empty gc-live bundle. In case of non-empty gc-live bundle,
behavior does not change.

Reviewed By: skatkov

Differential Revision: https://reviews.llvm.org/D88999
This commit is contained in:
Denis Antrushin 2020-10-08 01:32:50 +07:00
parent e1c38dd55d
commit 2b96dcebfa
2 changed files with 15 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
llvm/lib/CodeGen/SelectionDAG/StatepointLowering.cpp
View File

@ -557,6 +557,10 @@ lowerStatepointMetaArgs(SmallVectorImpl<SDValue> &Ops,
unsigned CurNumVRegs = 0;
auto canPassGCPtrOnVReg = [&](SDValue SDV) {
return !(willLowerDirectly(SDV) || SDV.getValueType().isVector());
};
auto processGCPtr = [&](const Value *V) {
SDValue PtrSD = Builder.getValue(V);
if (!LoweredGCPtrs.insert(PtrSD))
@ -566,7 +570,9 @@ lowerStatepointMetaArgs(SmallVectorImpl<SDValue> &Ops,
assert(!LowerAsVReg.count(PtrSD) && "must not have been seen");
if (LowerAsVReg.size() == MaxVRegPtrs)
return;
if (willLowerDirectly(PtrSD) || V->getType()->isVectorTy()) {
assert(V->getType()->isVectorTy() == PtrSD.getValueType().isVector() &&
"IR and SD types disagree");
if (!canPassGCPtrOnVReg(PtrSD)) {
LLVM_DEBUG(dbgs() << "direct/spill "; PtrSD.dump(&Builder.DAG));
return;
}
@ -593,8 +599,12 @@ lowerStatepointMetaArgs(SmallVectorImpl<SDValue> &Ops,
};
auto requireSpillSlot = [&](const Value *V) {
if (isGCValue(V))
return !LowerAsVReg.count(Builder.getValue(V));
if (isGCValue(V)) {
SDValue SDV = Builder.getValue(V);
if (!LoweredGCPtrs.empty())
return !LowerAsVReg.count(SDV);
return !MaxVRegPtrs || !canPassGCPtrOnVReg(SDV);
}
return !(LiveInDeopt || UseRegistersForDeoptValues);
};

6
llvm/test/CodeGen/X86/statepoint-vreg-details.ll
View File

@ -326,16 +326,14 @@ define void @test_duplicate_ir_values() gc "statepoint-example" personality i32*
;CHECK-VREG: %0:gr64 = STATEPOINT 1, 16, 5, %8, $edi, $rsi, $edx, $ecx, $r8d, 2, 0, 2, 0, 2, 0, 2, 1, killed %1(tied-def 0), 2, 0, 2, 1, 0, 0, csr_64, implicit-def $rsp, implicit-def $ssp, implicit-def $eax
;CHECK-VREG: JMP_1 %bb.1
;CHECK-VREG: bb.1.normal_continue:
;CHECK-VREG: MOV64mr %stack.0, 1, $noreg, 0, $noreg, %0 :: (store 8 into %stack.0)
;CHECK-VREG: %13:gr32 = MOV32ri 10
;CHECK-VREG: $edi = COPY %13
;CHECK-VREG: STATEPOINT 2882400000, 0, 1, @__llvm_deoptimize, $edi, 2, 0, 2, 2, 2, 2, 1, 8, %stack.0, 0, 1, 8, %stack.0, 0, 2, 0, 2, 0, 2, 0, csr_64, implicit-def $rsp, implicit-def $ssp :: (volatile load store 8 on %stack.0)
;CHECK-VREG: STATEPOINT 2882400000, 0, 1, @__llvm_deoptimize, $edi, 2, 0, 2, 2, 2, 2, %0, %0, 2, 0, 2, 0, 2, 0, csr_64, implicit-def $rsp, implicit-def $ssp
;CHECK-VREG: bb.2.exceptional_return (landing-pad):
;CHECK-VREG: EH_LABEL <mcsymbol >
;CHECK-VREG: MOV64mr %stack.0, 1, $noreg, 0, $noreg, %0 :: (store 8 into %stack.0)
;CHECK-VREG: %12:gr32 = MOV32ri -271
;CHECK-VREG: $edi = COPY %12
;CHECK-VREG: STATEPOINT 2882400000, 0, 1, @__llvm_deoptimize, $edi, 2, 0, 2, 0, 2, 1, 1, 8, %stack.0, 0, 2, 0, 2, 0, 2, 0, csr_64, implicit-def $rsp, implicit-def $ssp :: (volatile load store 8 on %stack.0)
;CHECK-VREG: STATEPOINT 2882400000, 0, 1, @__llvm_deoptimize, $edi, 2, 0, 2, 0, 2, 1, %0, 2, 0, 2, 0, 2, 0, csr_64, implicit-def $rsp, implicit-def $ssp
entry:
%local.0 = load i8 addrspace(1)*, i8 addrspace(1)* addrspace(1)* undef, align 8