diff options
Diffstat (limited to 'llvm/lib/Target/RISCV')
4 files changed, 44 insertions, 0 deletions
diff --git a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVAsmBackend.cpp b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVAsmBackend.cpp index 41a9c92..96e8afc 100644 --- a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVAsmBackend.cpp +++ b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVAsmBackend.cpp @@ -823,6 +823,7 @@ static bool relaxableFixupNeedsRelocation(const MCFixupKind Kind) { break; case RISCV::fixup_riscv_rvc_jump: case RISCV::fixup_riscv_rvc_branch: + case RISCV::fixup_riscv_rvc_imm: case RISCV::fixup_riscv_jal: return false; } diff --git a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVMCCodeEmitter.cpp b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVMCCodeEmitter.cpp index 6d587e6..5934c91 100644 --- a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVMCCodeEmitter.cpp +++ b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVMCCodeEmitter.cpp @@ -688,6 +688,7 @@ uint64_t RISCVMCCodeEmitter::getImmOpValue(const MCInst &MI, unsigned OpNo, // the `jal` again in the assembler. } else if (MIFrm == RISCVII::InstFormatCI) { FixupKind = RISCV::fixup_riscv_rvc_imm; + AsmRelaxToLinkerRelaxableWithFeature(RISCV::FeatureVendorXqcili); } else if (MIFrm == RISCVII::InstFormatI) { FixupKind = RISCV::fixup_riscv_12_i; } else if (MIFrm == RISCVII::InstFormatQC_EB) { diff --git a/llvm/lib/Target/RISCV/RISCVExpandAtomicPseudoInsts.cpp b/llvm/lib/Target/RISCV/RISCVExpandAtomicPseudoInsts.cpp index 98b636e..9bd66a4 100644 --- a/llvm/lib/Target/RISCV/RISCVExpandAtomicPseudoInsts.cpp +++ b/llvm/lib/Target/RISCV/RISCVExpandAtomicPseudoInsts.cpp @@ -373,6 +373,26 @@ static void doAtomicBinOpExpansion(const RISCVInstrInfo *TII, MachineInstr &MI, .addReg(ScratchReg) .addImm(-1); break; + case AtomicRMWInst::Max: + BuildMI(LoopMBB, DL, TII->get(RISCV::MAX), ScratchReg) + .addReg(DestReg) + .addReg(IncrReg); + break; + case AtomicRMWInst::Min: + BuildMI(LoopMBB, DL, TII->get(RISCV::MIN), ScratchReg) + .addReg(DestReg) + .addReg(IncrReg); + break; + case AtomicRMWInst::UMax: + BuildMI(LoopMBB, DL, TII->get(RISCV::MAXU), ScratchReg) + .addReg(DestReg) + .addReg(IncrReg); + break; + case AtomicRMWInst::UMin: + BuildMI(LoopMBB, DL, TII->get(RISCV::MINU), ScratchReg) + .addReg(DestReg) + .addReg(IncrReg); + break; } BuildMI(LoopMBB, DL, TII->get(getSCForRMW(Ordering, Width, STI)), ScratchReg) .addReg(ScratchReg) @@ -682,6 +702,9 @@ bool RISCVExpandAtomicPseudo::expandAtomicMinMaxOp( MachineBasicBlock &MBB, MachineBasicBlock::iterator MBBI, AtomicRMWInst::BinOp BinOp, bool IsMasked, int Width, MachineBasicBlock::iterator &NextMBBI) { + // Using MIN(U)/MAX(U) is preferrable if permitted + if (STI->hasPermissiveZalrsc() && STI->hasStdExtZbb() && !IsMasked) + return expandAtomicBinOp(MBB, MBBI, BinOp, IsMasked, Width, NextMBBI); MachineInstr &MI = *MBBI; DebugLoc DL = MI.getDebugLoc(); diff --git a/llvm/lib/Target/RISCV/RISCVFeatures.td b/llvm/lib/Target/RISCV/RISCVFeatures.td index 2754d78..b4556f6 100644 --- a/llvm/lib/Target/RISCV/RISCVFeatures.td +++ b/llvm/lib/Target/RISCV/RISCVFeatures.td @@ -1906,6 +1906,25 @@ def FeatureForcedAtomics : SubtargetFeature< def HasAtomicLdSt : Predicate<"Subtarget->hasStdExtZalrsc() || Subtarget->hasForcedAtomics()">; +// The RISC-V Unprivileged Architecture - ISA Volume 1 (Version: 20250508) +// [https://docs.riscv.org/reference/isa/_attachments/riscv-unprivileged.pdf] +// in section 13.3. Eventual Success of Store-Conditional Instructions, defines +// _constrained_ LR/SC loops: +// The dynamic code executed between the LR and SC instructions can only +// contain instructions from the base ''I'' instruction set, excluding loads, +// stores, backward jumps, taken backward branches, JALR, FENCE, and SYSTEM +// instructions. Compressed forms of the aforementioned ''I'' instructions in +// the Zca and Zcb extensions are also permitted. +// LR/SC loops that do not adhere to the above are _unconstrained_ LR/SC loops, +// and success is implementation specific. For implementations which know that +// non-base instructions (such as the ''B'' extension) will not violate any +// forward progress guarantees, using these instructions to reduce the LR/SC +// sequence length is desirable. +def FeaturePermissiveZalrsc + : SubtargetFeature< + "permissive-zalrsc", "HasPermissiveZalrsc", "true", + "Implementation permits non-base instructions between LR/SC pairs">; + def FeatureTaggedGlobals : SubtargetFeature<"tagged-globals", "AllowTaggedGlobals", "true", "Use an instruction sequence for taking the address of a global " |