[llvm] [llvm] Fix enum-enum bitwise and arithmetic conversions for C++26 (PR #228945)
via llvm-commits
llvm-commits at lists.llvm.org
Sun Oct 4 15:30:17 PDT 2026
https://github.com/rdong8 created https://github.com/llvm/llvm-project/pull/228945
Fixes arithmetic operations between enumerators of different enum types that are now rejected under C++26.
Assisted by AI.
Related:
- https://github.com/llvm/llvm-project/pull/223284
- https://discourse.llvm.org/t/policy-on-supporting-newer-c-standard-in-llvm-codebase/88114
>From 6f6aff0c499fd2fae808a1d63e293eefd2aa6fe7 Mon Sep 17 00:00:00 2001
From: Richard Dong <rdong8 at protonmail.com>
Date: Sun, 4 Oct 2026 20:36:39 +0000
Subject: [PATCH] [llvm] Fix enum-enum bitwise and arithmetic conversions for
C++26
Fix operations involving distinct enum types across LLVM target descriptors,
MC, and CodeGen that are deprecated or rejected under C++26:
- Use llvm::to_underlying for fixup arithmetic and MachO section attributes.
- Use explicit comparison for InlineAsm dialect flags rather than enum arithmetic.
- Define operator& for PPC Predicate and BranchHintBit.
---
llvm/lib/CodeGen/GlobalISel/InlineAsmLowering.cpp | 3 ++-
llvm/lib/CodeGen/SelectionDAG/FastISel.cpp | 3 ++-
llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | 3 ++-
llvm/lib/MC/MCObjectFileInfo.cpp | 4 ++--
llvm/lib/MC/MCParser/DarwinAsmParser.cpp | 8 ++++----
llvm/lib/Target/AMDGPU/SIFrameLowering.cpp | 4 ++--
llvm/lib/Target/Hexagon/HexagonISelDAGToDAGHVX.cpp | 2 +-
.../LoongArch/MCTargetDesc/LoongArchAsmBackend.cpp | 2 +-
.../LoongArch/MCTargetDesc/LoongArchMCCodeEmitter.cpp | 2 +-
.../lib/Target/PowerPC/MCTargetDesc/PPCELFStreamer.cpp | 2 +-
llvm/lib/Target/PowerPC/MCTargetDesc/PPCPredicates.h | 10 ++++++++++
llvm/lib/Target/RISCV/MCTargetDesc/RISCVAsmBackend.cpp | 2 +-
.../SystemZ/MCTargetDesc/SystemZMCCodeEmitter.cpp | 2 +-
llvm/lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp | 2 +-
14 files changed, 31 insertions(+), 18 deletions(-)
diff --git a/llvm/lib/CodeGen/GlobalISel/InlineAsmLowering.cpp b/llvm/lib/CodeGen/GlobalISel/InlineAsmLowering.cpp
index 19eae930cc26b10..01bd7c28595fec8 100644
--- a/llvm/lib/CodeGen/GlobalISel/InlineAsmLowering.cpp
+++ b/llvm/lib/CodeGen/GlobalISel/InlineAsmLowering.cpp
@@ -69,7 +69,8 @@ class ExtraFlags {
Flags |= InlineAsm::Extra_MayUnwind;
if (CB.isConvergent())
Flags |= InlineAsm::Extra_IsConvergent;
- Flags |= IA->getDialect() * InlineAsm::Extra_AsmDialect;
+ if (IA->getDialect() == InlineAsm::AD_Intel)
+ Flags |= InlineAsm::Extra_AsmDialect;
}
void update(const TargetLowering::AsmOperandInfo &OpInfo) {
diff --git a/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp b/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp
index 4f3913907050812..19f1f328d309b1b 100644
--- a/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp
@@ -1171,7 +1171,8 @@ bool FastISel::selectCall(const User *I) {
ExtraInfo |= InlineAsm::Extra_MayUnwind;
if (Call->isConvergent())
ExtraInfo |= InlineAsm::Extra_IsConvergent;
- ExtraInfo |= IA->getDialect() * InlineAsm::Extra_AsmDialect;
+ if (IA->getDialect() == InlineAsm::AD_Intel)
+ ExtraInfo |= InlineAsm::Extra_AsmDialect;
MachineInstrBuilder MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, MIMD,
TII.get(TargetOpcode::INLINEASM));
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
index dfbf9a401b53eab..3f3a316ba418ff2 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp
@@ -10396,7 +10396,8 @@ class ExtraFlags {
Flags |= InlineAsm::Extra_MayUnwind;
if (Call.isConvergent())
Flags |= InlineAsm::Extra_IsConvergent;
- Flags |= IA->getDialect() * InlineAsm::Extra_AsmDialect;
+ if (IA->getDialect() == InlineAsm::AD_Intel)
+ Flags |= InlineAsm::Extra_AsmDialect;
}
void update(const TargetLowering::AsmOperandInfo &OpInfo) {
diff --git a/llvm/lib/MC/MCObjectFileInfo.cpp b/llvm/lib/MC/MCObjectFileInfo.cpp
index 41e5adf304d3560..86d2388147756a6 100644
--- a/llvm/lib/MC/MCObjectFileInfo.cpp
+++ b/llvm/lib/MC/MCObjectFileInfo.cpp
@@ -66,7 +66,7 @@ static bool useCompactUnwind(const Triple &T) {
void MCObjectFileInfo::initMachOMCObjectFileInfo(const Triple &T) {
EHFrameSection = Ctx->getMachOSection(
"__TEXT", "__eh_frame",
- MachO::S_COALESCED | MachO::S_ATTR_NO_TOC |
+ llvm::to_underlying(MachO::S_COALESCED) | MachO::S_ATTR_NO_TOC |
MachO::S_ATTR_STRIP_STATIC_SYMS | MachO::S_ATTR_LIVE_SUPPORT,
SectionKind::getReadOnly());
@@ -160,7 +160,7 @@ void MCObjectFileInfo::initMachOMCObjectFileInfo(const Triple &T) {
if (ArchTy == Triple::ppc || ArchTy == Triple::ppc64) {
TextCoalSection
= Ctx->getMachOSection("__TEXT", "__textcoal_nt",
- MachO::S_COALESCED |
+ llvm::to_underlying(MachO::S_COALESCED) |
MachO::S_ATTR_PURE_INSTRUCTIONS,
SectionKind::getText());
ConstTextCoalSection
diff --git a/llvm/lib/MC/MCParser/DarwinAsmParser.cpp b/llvm/lib/MC/MCParser/DarwinAsmParser.cpp
index ba6813c142266f9..25e6cab7d9fee50 100644
--- a/llvm/lib/MC/MCParser/DarwinAsmParser.cpp
+++ b/llvm/lib/MC/MCParser/DarwinAsmParser.cpp
@@ -269,7 +269,7 @@ class DarwinAsmParser : public MCAsmParserExtension {
bool parseSectionDirectiveSymbolStub(StringRef, SMLoc) {
return parseSectionSwitch("__TEXT","__symbol_stub",
- MachO::S_SYMBOL_STUBS |
+ llvm::to_underlying(MachO::S_SYMBOL_STUBS) |
MachO::S_ATTR_PURE_INSTRUCTIONS,
// FIXME: Different on PPC and ARM.
0, 16);
@@ -277,7 +277,7 @@ class DarwinAsmParser : public MCAsmParserExtension {
bool parseSectionDirectivePICSymbolStub(StringRef, SMLoc) {
return parseSectionSwitch("__TEXT","__picsymbol_stub",
- MachO::S_SYMBOL_STUBS |
+ llvm::to_underlying(MachO::S_SYMBOL_STUBS) |
MachO::S_ATTR_PURE_INSTRUCTIONS, 0, 26);
}
@@ -365,13 +365,13 @@ class DarwinAsmParser : public MCAsmParserExtension {
bool parseSectionDirectiveObjCClsRefs(StringRef, SMLoc) {
return parseSectionSwitch("__OBJC", "__cls_refs",
MachO::S_ATTR_NO_DEAD_STRIP |
- MachO::S_LITERAL_POINTERS, 4);
+ llvm::to_underlying(MachO::S_LITERAL_POINTERS), 4);
}
bool parseSectionDirectiveObjCMessageRefs(StringRef, SMLoc) {
return parseSectionSwitch("__OBJC", "__message_refs",
MachO::S_ATTR_NO_DEAD_STRIP |
- MachO::S_LITERAL_POINTERS, 4);
+ llvm::to_underlying(MachO::S_LITERAL_POINTERS), 4);
}
bool parseSectionDirectiveObjCSymbols(StringRef, SMLoc) {
diff --git a/llvm/lib/Target/AMDGPU/SIFrameLowering.cpp b/llvm/lib/Target/AMDGPU/SIFrameLowering.cpp
index 364d8f07b6df25e..eff041737b4050a 100644
--- a/llvm/lib/Target/AMDGPU/SIFrameLowering.cpp
+++ b/llvm/lib/Target/AMDGPU/SIFrameLowering.cpp
@@ -81,7 +81,7 @@ static MCCFIInstruction createScaledCFAInPrivateWave(const GCNSubtarget &ST,
<< uint8_t(dwarf::DW_OP_lit0 + WavefrontSizeLog2)
<< uint8_t(dwarf::DW_OP_shl)
<< uint8_t(dwarf::DW_OP_lit0 +
- dwarf::DW_ASPACE_LLVM_AMDGPU_private_wave)
+ llvm::to_underlying(dwarf::DW_ASPACE_LLVM_AMDGPU_private_wave))
<< uint8_t(dwarf::DW_OP_LLVM_user)
<< uint8_t(dwarf::DW_OP_LLVM_form_aspace_address);
@@ -780,7 +780,7 @@ void SIFrameLowering::emitEntryFunctionPrologue(MachineFunction &MF,
4, // length
static_cast<char>(dwarf::DW_OP_lit0),
static_cast<char>(dwarf::DW_OP_lit0 +
- dwarf::DW_ASPACE_LLVM_AMDGPU_private_wave),
+ llvm::to_underlying(dwarf::DW_ASPACE_LLVM_AMDGPU_private_wave)),
static_cast<char>(dwarf::DW_OP_LLVM_user),
static_cast<char>(dwarf::DW_OP_LLVM_form_aspace_address)};
static StringRef CFAEncodedInstUserOps =
diff --git a/llvm/lib/Target/Hexagon/HexagonISelDAGToDAGHVX.cpp b/llvm/lib/Target/Hexagon/HexagonISelDAGToDAGHVX.cpp
index 129f3071a3a884e..088cebe1d53d5d5 100644
--- a/llvm/lib/Target/Hexagon/HexagonISelDAGToDAGHVX.cpp
+++ b/llvm/lib/Target/Hexagon/HexagonISelDAGToDAGHVX.cpp
@@ -628,7 +628,7 @@ struct OpRef {
assert(!R.isValue());
return OpRef(R.OpN & (Undef | Index | HiHalf));
}
- static OpRef undef(MVT Ty) { return OpRef(Undef | Ty.SimpleTy); }
+ static OpRef undef(MVT Ty) { return OpRef(Undef | llvm::to_underlying(Ty.SimpleTy)); }
// Direct value.
SDValue OpV = SDValue();
diff --git a/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchAsmBackend.cpp b/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchAsmBackend.cpp
index 4581da3c7b9c30f..1895fa2eb9920c0 100644
--- a/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchAsmBackend.cpp
+++ b/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchAsmBackend.cpp
@@ -252,7 +252,7 @@ bool LoongArchAsmBackend::relaxAlign(MCFragment &F, unsigned &Size) {
Ctx);
}
MCFixup Fixup =
- MCFixup::create(0, Expr, FirstLiteralRelocationKind + ELF::R_LARCH_ALIGN);
+ MCFixup::create(0, Expr, FirstLiteralRelocationKind + llvm::to_underlying(ELF::R_LARCH_ALIGN));
F.setVarFixups({Fixup});
F.setLinkerRelaxable();
return true;
diff --git a/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchMCCodeEmitter.cpp b/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchMCCodeEmitter.cpp
index 8146a15eba29573..3a77bd154ca2c9f 100644
--- a/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchMCCodeEmitter.cpp
+++ b/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchMCCodeEmitter.cpp
@@ -166,7 +166,7 @@ LoongArchMCCodeEmitter::getExprOpValue(const MCInst &MI, const MCOperand &MO,
// `la.abs`.
Fixups.push_back(
MCFixup::create(0, MCConstantExpr::create(0, Ctx),
- FirstLiteralRelocationKind + ELF::R_LARCH_MARK_LA));
+ FirstLiteralRelocationKind + llvm::to_underlying(ELF::R_LARCH_MARK_LA)));
[[fallthrough]];
case ELF::R_LARCH_ABS_HI20:
FixupKind = LoongArch::fixup_loongarch_abs_hi20;
diff --git a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCELFStreamer.cpp b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCELFStreamer.cpp
index 7b2d2be503d7275..0a64998a213c79a 100644
--- a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCELFStreamer.cpp
+++ b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCELFStreamer.cpp
@@ -157,7 +157,7 @@ void PPCELFStreamer::emitGOTToPCRelReloc(const MCInst &Inst) {
MCFragment *F = LabelSym->getFragment();
F->addFixup(
MCFixup::create(LabelSym->getOffset() - 8, SubExpr2,
- FirstLiteralRelocationKind + ELF::R_PPC64_PCREL_OPT));
+ FirstLiteralRelocationKind + llvm::to_underlying(ELF::R_PPC64_PCREL_OPT)));
emitLabel(CurrentLocation, Inst.getLoc());
}
diff --git a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCPredicates.h b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCPredicates.h
index d686a8ea2a2281a..cd7317927411061 100644
--- a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCPredicates.h
+++ b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCPredicates.h
@@ -13,6 +13,8 @@
#ifndef LLVM_LIB_TARGET_POWERPC_MCTARGETDESC_PPCPREDICATES_H
#define LLVM_LIB_TARGET_POWERPC_MCTARGETDESC_PPCPREDICATES_H
+#include "llvm/ADT/STLForwardCompat.h"
+
// GCC #defines PPC on Linux but we use it as our namespace name
#undef PPC
@@ -66,6 +68,14 @@ namespace PPC {
BR_HINT_MASK = 0X3
};
+ inline unsigned operator&(Predicate P, BranchHintBit B) {
+ return llvm::to_underlying(P) & llvm::to_underlying(B);
+ }
+
+ inline unsigned operator&(BranchHintBit B, Predicate P) {
+ return P & B;
+ }
+
/// Invert the specified predicate. != -> ==, < -> >=.
Predicate InvertPredicate(Predicate Opcode);
diff --git a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVAsmBackend.cpp b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVAsmBackend.cpp
index 315d129aeb5fbac..9c9fb67968a7d4a 100644
--- a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVAsmBackend.cpp
+++ b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVAsmBackend.cpp
@@ -350,7 +350,7 @@ bool RISCVAsmBackend::relaxAlign(MCFragment &F, unsigned &Size) {
Size = F.getAlignment().value() - MinNopLen;
auto *Expr = MCConstantExpr::create(Size, getContext());
MCFixup Fixup =
- MCFixup::create(0, Expr, FirstLiteralRelocationKind + ELF::R_RISCV_ALIGN);
+ MCFixup::create(0, Expr, FirstLiteralRelocationKind + llvm::to_underlying(ELF::R_RISCV_ALIGN));
F.setVarFixups({Fixup});
F.setLinkerRelaxable();
return true;
diff --git a/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZMCCodeEmitter.cpp b/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZMCCodeEmitter.cpp
index 383c96e8cca7346..bd0bcabb0e2399c 100644
--- a/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZMCCodeEmitter.cpp
+++ b/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZMCCodeEmitter.cpp
@@ -172,7 +172,7 @@ uint64_t SystemZMCCodeEmitter::getImmOpValue(const MCInst &MI, unsigned OpNum,
unsigned MIBitSize = MCII.get(MI.getOpcode()).getSize() * 8;
uint32_t RawBitOffset = getOperandBitOffset(MI, OpNum, STI);
unsigned OpBitSize =
- SystemZ::MCFixupKindInfos[Kind - FirstTargetFixupKind].TargetSize;
+ SystemZ::MCFixupKindInfos[llvm::to_underlying(Kind) - FirstTargetFixupKind].TargetSize;
uint32_t BitOffset = MIBitSize - RawBitOffset - OpBitSize;
addFixup(Fixups, BitOffset >> 3, MO.getExpr(), Kind);
return 0;
diff --git a/llvm/lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp b/llvm/lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp
index ab535c81dbf42c8..8f2374426b8061b 100644
--- a/llvm/lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp
+++ b/llvm/lib/Target/X86/MCTargetDesc/X86MCCodeEmitter.cpp
@@ -542,7 +542,7 @@ void X86MCCodeEmitter::emitImmediate(const MCOperand &DispOp, SMLoc Loc,
assert(ImmOffset == 0);
if (Size == 8) {
- FixupKind = FirstLiteralRelocationKind + ELF::R_X86_64_GOTPC64;
+ FixupKind = FirstLiteralRelocationKind + llvm::to_underlying(ELF::R_X86_64_GOTPC64);
} else {
assert(Size == 4);
FixupKind = X86::reloc_global_offset_table;
More information about the llvm-commits
mailing list