[llvm] dc452a7 - Revert "[RISCV] Enable the LocalStackSlotAllocation pass support"
Craig Topper via llvm-commits
llvm-commits at lists.llvm.org
Tue Nov 1 20:20:32 PDT 2022
Author: Craig Topper
Date: 2022-11-01T20:04:07-07:00
New Revision: dc452a76c27ac0d0a89fb7a30767023b5afcf20c
URL: https://github.com/llvm/llvm-project/commit/dc452a76c27ac0d0a89fb7a30767023b5afcf20c
DIFF: https://github.com/llvm/llvm-project/commit/dc452a76c27ac0d0a89fb7a30767023b5afcf20c.diff
LOG: Revert "[RISCV] Enable the LocalStackSlotAllocation pass support"
This reverts commit 82c820b95cf7ec284baf182cf838ca9e26758098.
This failed llvm-testsuite in our downstream and a similar issue
was reported by @rogfer01.
Added:
Modified:
llvm/lib/Target/RISCV/RISCVFrameLowering.h
llvm/lib/Target/RISCV/RISCVRegisterInfo.cpp
llvm/lib/Target/RISCV/RISCVRegisterInfo.h
llvm/test/CodeGen/RISCV/local-stack-slot-allocation.ll
Removed:
################################################################################
diff --git a/llvm/lib/Target/RISCV/RISCVFrameLowering.h b/llvm/lib/Target/RISCV/RISCVFrameLowering.h
index 70cf1e55fb35e..8b13eb0acd11c 100644
--- a/llvm/lib/Target/RISCV/RISCVFrameLowering.h
+++ b/llvm/lib/Target/RISCV/RISCVFrameLowering.h
@@ -73,12 +73,6 @@ class RISCVFrameLowering : public TargetFrameLowering {
bool isSupportedStackID(TargetStackID::Value ID) const override;
TargetStackID::Value getStackIDForScalableVectors() const override;
- bool isStackIdSafeForLocalArea(unsigned StackId) const override {
- // We don't support putting RISCV Vector objects into the pre-allocated
- // local frame block at the moment.
- return StackId != TargetStackID::ScalableVector;
- }
-
protected:
const RISCVSubtarget &STI;
diff --git a/llvm/lib/Target/RISCV/RISCVRegisterInfo.cpp b/llvm/lib/Target/RISCV/RISCVRegisterInfo.cpp
index fb15a133c143d..5066c0ced0ce9 100644
--- a/llvm/lib/Target/RISCV/RISCVRegisterInfo.cpp
+++ b/llvm/lib/Target/RISCV/RISCVRegisterInfo.cpp
@@ -295,113 +295,6 @@ void RISCVRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
}
}
-bool RISCVRegisterInfo::requiresVirtualBaseRegisters(
- const MachineFunction &MF) const {
- return true;
-}
-
-// Returns true if the instruction's frame index reference would be better
-// served by a base register other than FP or SP.
-// Used by LocalStackSlotAllocation pass to determine which frame index
-// references it should create new base registers for.
-bool RISCVRegisterInfo::needsFrameBaseReg(MachineInstr *MI,
- int64_t Offset) const {
- unsigned FIOperandNum = 0;
- for (; !MI->getOperand(FIOperandNum).isFI(); FIOperandNum++)
- assert(FIOperandNum < MI->getNumOperands() &&
- "Instr doesn't have FrameIndex operand");
-
- // For RISC-V, The machine instructions that include a FrameIndex operand
- // are load/store, ADDI instructions.
- unsigned MIFrm = RISCVII::getFormat(MI->getDesc().TSFlags);
- if (MIFrm != RISCVII::InstFormatI && MIFrm != RISCVII::InstFormatS)
- return false;
-
- const MachineFunction &MF = *MI->getMF();
- const MachineFrameInfo &MFI = MF.getFrameInfo();
- const RISCVFrameLowering *TFI = getFrameLowering(MF);
- const MachineRegisterInfo &MRI = MF.getRegInfo();
- unsigned CalleeSavedSize = 0;
- Offset += getFrameIndexInstrOffset(MI, FIOperandNum);
-
- // Estimate the stack size used to store callee saved registers(
- // excludes reserved registers).
- BitVector ReservedRegs = getReservedRegs(MF);
- for (const MCPhysReg *R = MRI.getCalleeSavedRegs(); MCPhysReg Reg = *R; ++R) {
- if (!ReservedRegs.test(Reg))
- CalleeSavedSize += getSpillSize(*getMinimalPhysRegClass(Reg));
- }
-
- int64_t MaxFPOffset = Offset - CalleeSavedSize;
- if (TFI->hasFP(MF) && !shouldRealignStack(MF))
- return !isFrameOffsetLegal(MI, RISCV::X8, MaxFPOffset);
-
- // Assume 128 bytes spill slots size to estimate the maximum possible
- // offset relative to the stack pointer.
- // FIXME: The 128 is copied from ARM. We should run some statistics and pick a
- // real one for RISC-V.
- int64_t MaxSPOffset = Offset + 128;
- MaxSPOffset += MFI.getLocalFrameSize();
- return !isFrameOffsetLegal(MI, RISCV::X2, MaxSPOffset);
-}
-
-// Determine whether a given base register plus offset immediate is
-// encodable to resolve a frame index.
-bool RISCVRegisterInfo::isFrameOffsetLegal(const MachineInstr *MI,
- Register BaseReg,
- int64_t Offset) const {
- return isInt<12>(Offset);
-}
-
-// Insert defining instruction(s) for a pointer to FrameIdx before
-// insertion point I.
-// Return materialized frame pointer.
-Register RISCVRegisterInfo::materializeFrameBaseRegister(MachineBasicBlock *MBB,
- int FrameIdx,
- int64_t Offset) const {
- MachineBasicBlock::iterator MBBI = MBB->begin();
- DebugLoc DL;
- if (MBBI != MBB->end())
- DL = MBBI->getDebugLoc();
- MachineFunction *MF = MBB->getParent();
- MachineRegisterInfo &MFI = MF->getRegInfo();
- const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
-
- Register BaseReg = MFI.createVirtualRegister(&RISCV::GPRRegClass);
- BuildMI(*MBB, MBBI, DL, TII->get(RISCV::ADDI), BaseReg)
- .addFrameIndex(FrameIdx)
- .addImm(Offset);
- return BaseReg;
-}
-
-// Resolve a frame index operand of an instruction to reference the
-// indicated base register plus offset instead.
-void RISCVRegisterInfo::resolveFrameIndex(MachineInstr &MI, Register BaseReg,
- int64_t Offset) const {
- unsigned FIOperandNum = 0;
- while (!MI.getOperand(FIOperandNum).isFI())
- FIOperandNum++;
- assert(FIOperandNum < MI.getNumOperands() &&
- "Instr does not have a FrameIndex operand!");
- Offset += getFrameIndexInstrOffset(&MI, FIOperandNum);
- // FrameIndex Operands are always represented as a
- // register followed by an immediate.
- MI.getOperand(FIOperandNum).ChangeToRegister(BaseReg, false);
- MI.getOperand(FIOperandNum + 1).ChangeToImmediate(Offset);
-}
-
-// Get the offset from the referenced frame index in the instruction,
-// if there is one.
-int64_t RISCVRegisterInfo::getFrameIndexInstrOffset(const MachineInstr *MI,
- int Idx) const {
- assert((RISCVII::getFormat(MI->getDesc().TSFlags) == RISCVII::InstFormatI ||
- RISCVII::getFormat(MI->getDesc().TSFlags) == RISCVII::InstFormatS) &&
- "The MI must be I or S format.");
- assert(MI->getOperand(Idx).isFI() && "The Idx'th operand of MI is not a "
- "FrameIndex operand");
- return MI->getOperand(Idx + 1).getImm();
-}
-
Register RISCVRegisterInfo::getFrameRegister(const MachineFunction &MF) const {
const TargetFrameLowering *TFI = getFrameLowering(MF);
return TFI->hasFP(MF) ? RISCV::X8 : RISCV::X2;
diff --git a/llvm/lib/Target/RISCV/RISCVRegisterInfo.h b/llvm/lib/Target/RISCV/RISCVRegisterInfo.h
index afdb75cfd233c..1c66e94871f8f 100644
--- a/llvm/lib/Target/RISCV/RISCVRegisterInfo.h
+++ b/llvm/lib/Target/RISCV/RISCVRegisterInfo.h
@@ -38,22 +38,6 @@ struct RISCVRegisterInfo : public RISCVGenRegisterInfo {
bool hasReservedSpillSlot(const MachineFunction &MF, Register Reg,
int &FrameIdx) const override;
- bool requiresVirtualBaseRegisters(const MachineFunction &MF) const override;
-
- bool needsFrameBaseReg(MachineInstr *MI, int64_t Offset) const override;
-
- bool isFrameOffsetLegal(const MachineInstr *MI, Register BaseReg,
- int64_t Offset) const override;
-
- Register materializeFrameBaseRegister(MachineBasicBlock *MBB, int FrameIdx,
- int64_t Offset) const override;
-
- void resolveFrameIndex(MachineInstr &MI, Register BaseReg,
- int64_t Offset) const override;
-
- int64_t getFrameIndexInstrOffset(const MachineInstr *MI,
- int Idx) const override;
-
void eliminateFrameIndex(MachineBasicBlock::iterator MI, int SPAdj,
unsigned FIOperandNum,
RegScavenger *RS = nullptr) const override;
diff --git a/llvm/test/CodeGen/RISCV/local-stack-slot-allocation.ll b/llvm/test/CodeGen/RISCV/local-stack-slot-allocation.ll
index df300170f4360..544834a5d87db 100644
--- a/llvm/test/CodeGen/RISCV/local-stack-slot-allocation.ll
+++ b/llvm/test/CodeGen/RISCV/local-stack-slot-allocation.ll
@@ -5,6 +5,7 @@
; This test case test the LocalStackSlotAllocation pass that use a base register
; for the frame index that its offset is out-of-range (for RISC-V. the immediate
; is 12 bits for the load store instruction (excludes vector load / store))
+; TODO: Enable LocalStackSlotAllocation pass.
define void @use_frame_base_reg() {
; RV32I-LABEL: use_frame_base_reg:
; RV32I: # %bb.0:
@@ -13,9 +14,12 @@ define void @use_frame_base_reg() {
; RV32I-NEXT: sub sp, sp, a0
; RV32I-NEXT: .cfi_def_cfa_offset 100016
; RV32I-NEXT: lui a0, 24
+; RV32I-NEXT: addi a0, a0, 1708
+; RV32I-NEXT: add a0, sp, a0
+; RV32I-NEXT: lb a0, 0(a0)
+; RV32I-NEXT: lui a0, 24
; RV32I-NEXT: addi a0, a0, 1704
; RV32I-NEXT: add a0, sp, a0
-; RV32I-NEXT: lb a1, 4(a0)
; RV32I-NEXT: lb a0, 0(a0)
; RV32I-NEXT: lui a0, 24
; RV32I-NEXT: addi a0, a0, 1712
@@ -29,9 +33,12 @@ define void @use_frame_base_reg() {
; RV64I-NEXT: sub sp, sp, a0
; RV64I-NEXT: .cfi_def_cfa_offset 100016
; RV64I-NEXT: lui a0, 24
+; RV64I-NEXT: addiw a0, a0, 1708
+; RV64I-NEXT: add a0, sp, a0
+; RV64I-NEXT: lb a0, 0(a0)
+; RV64I-NEXT: lui a0, 24
; RV64I-NEXT: addiw a0, a0, 1704
; RV64I-NEXT: add a0, sp, a0
-; RV64I-NEXT: lb a1, 4(a0)
; RV64I-NEXT: lb a0, 0(a0)
; RV64I-NEXT: lui a0, 24
; RV64I-NEXT: addiw a0, a0, 1712
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