[RISCV][MC] Pass MCSubtargetInfo down to shouldForceRelocation and evaluateTargetFixup. (#73721)

topperc · web-flow · commit e87f33d9ce78 · 2023-12-07T13:17:58.000-08:00
Instead of using the STI stored in RISCVAsmBackend, try to get it from the MCFragment. This addresses the issue raised here https://discourse.llvm.org/t/possible-problem-related-to-subtarget-usage/75283
diff --git a/llvm/include/llvm/MC/MCAsmBackend.h b/llvm/include/llvm/MC/MCAsmBackend.h
@@ -101,7 +101,8 @@ class MCAsmBackend {
   /// Hook to check if a relocation is needed for some target specific reason.
   virtual bool shouldForceRelocation(const MCAssembler &Asm,
                                      const MCFixup &Fixup,
-                                     const MCValue &Target) {
+                                     const MCValue &Target,
+                                     const MCSubtargetInfo *STI) {
     return false;
   }
 
@@ -124,7 +125,8 @@ class MCAsmBackend {
   virtual bool evaluateTargetFixup(const MCAssembler &Asm,
                                    const MCAsmLayout &Layout,
                                    const MCFixup &Fixup, const MCFragment *DF,
-                                   const MCValue &Target, uint64_t &Value,
+                                   const MCValue &Target,
+                                   const MCSubtargetInfo *STI, uint64_t &Value,
                                    bool &WasForced) {
     llvm_unreachable("Need to implement hook if target has custom fixups");
   }
diff --git a/llvm/include/llvm/MC/MCAssembler.h b/llvm/include/llvm/MC/MCAssembler.h
@@ -185,7 +185,8 @@ class MCAssembler {
   /// relocation.
   bool evaluateFixup(const MCAsmLayout &Layout, const MCFixup &Fixup,
                      const MCFragment *DF, MCValue &Target,
-                     uint64_t &Value, bool &WasForced) const;
+                     const MCSubtargetInfo *STI, uint64_t &Value,
+                     bool &WasForced) const;
 
   /// Check whether a fixup can be satisfied, or whether it needs to be relaxed
   /// (increased in size, in order to hold its value correctly).
@@ -221,8 +222,10 @@ class MCAssembler {
   /// finishLayout - Finalize a layout, including fragment lowering.
   void finishLayout(MCAsmLayout &Layout);
 
-  std::tuple<MCValue, uint64_t, bool>
-  handleFixup(const MCAsmLayout &Layout, MCFragment &F, const MCFixup &Fixup);
+  std::tuple<MCValue, uint64_t, bool> handleFixup(const MCAsmLayout &Layout,
+                                                  MCFragment &F,
+                                                  const MCFixup &Fixup,
+                                                  const MCSubtargetInfo *STI);
 
 public:
   struct Symver {
diff --git a/llvm/lib/MC/MCAssembler.cpp b/llvm/lib/MC/MCAssembler.cpp
@@ -193,9 +193,9 @@ const MCSymbol *MCAssembler::getAtom(const MCSymbol &S) const {
   return S.getFragment()->getAtom();
 }
 
-bool MCAssembler::evaluateFixup(const MCAsmLayout &Layout,
-                                const MCFixup &Fixup, const MCFragment *DF,
-                                MCValue &Target, uint64_t &Value,
+bool MCAssembler::evaluateFixup(const MCAsmLayout &Layout, const MCFixup &Fixup,
+                                const MCFragment *DF, MCValue &Target,
+                                const MCSubtargetInfo *STI, uint64_t &Value,
                                 bool &WasForced) const {
   ++stats::evaluateFixup;
 
@@ -227,7 +227,7 @@ bool MCAssembler::evaluateFixup(const MCAsmLayout &Layout,
 
   if (IsTarget)
     return getBackend().evaluateTargetFixup(*this, Layout, Fixup, DF, Target,
-                                            Value, WasForced);
+                                            STI, Value, WasForced);
 
   unsigned FixupFlags = getBackendPtr()->getFixupKindInfo(Fixup.getKind()).Flags;
   bool IsPCRel = getBackendPtr()->getFixupKindInfo(Fixup.getKind()).Flags &
@@ -282,7 +282,8 @@ bool MCAssembler::evaluateFixup(const MCAsmLayout &Layout,
   }
 
   // Let the backend force a relocation if needed.
-  if (IsResolved && getBackend().shouldForceRelocation(*this, Fixup, Target)) {
+  if (IsResolved &&
+      getBackend().shouldForceRelocation(*this, Fixup, Target, STI)) {
     IsResolved = false;
     WasForced = true;
   }
@@ -796,13 +797,13 @@ void MCAssembler::writeSectionData(raw_ostream &OS, const MCSection *Sec,
 
 std::tuple<MCValue, uint64_t, bool>
 MCAssembler::handleFixup(const MCAsmLayout &Layout, MCFragment &F,
-                         const MCFixup &Fixup) {
+                         const MCFixup &Fixup, const MCSubtargetInfo *STI) {
   // Evaluate the fixup.
   MCValue Target;
   uint64_t FixedValue;
   bool WasForced;
-  bool IsResolved = evaluateFixup(Layout, Fixup, &F, Target, FixedValue,
-                                  WasForced);
+  bool IsResolved =
+      evaluateFixup(Layout, Fixup, &F, Target, STI, FixedValue, WasForced);
   if (!IsResolved) {
     // The fixup was unresolved, we need a relocation. Inform the object
     // writer of the relocation, and give it an opportunity to adjust the
@@ -936,7 +937,7 @@ void MCAssembler::layout(MCAsmLayout &Layout) {
         bool IsResolved;
         MCValue Target;
         std::tie(Target, FixedValue, IsResolved) =
-            handleFixup(Layout, Frag, Fixup);
+            handleFixup(Layout, Frag, Fixup, STI);
         getBackend().applyFixup(*this, Fixup, Target, Contents, FixedValue,
                                 IsResolved, STI);
       }
@@ -960,7 +961,8 @@ bool MCAssembler::fixupNeedsRelaxation(const MCFixup &Fixup,
   MCValue Target;
   uint64_t Value;
   bool WasForced;
-  bool Resolved = evaluateFixup(Layout, Fixup, DF, Target, Value, WasForced);
+  bool Resolved = evaluateFixup(Layout, Fixup, DF, Target,
+                                DF->getSubtargetInfo(), Value, WasForced);
   if (Target.getSymA() &&
       Target.getSymA()->getKind() == MCSymbolRefExpr::VK_X86_ABS8 &&
       Fixup.getKind() == FK_Data_1)
diff --git a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64AsmBackend.cpp b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64AsmBackend.cpp
@@ -100,7 +100,8 @@ class AArch64AsmBackend : public MCAsmBackend {
   unsigned getFixupKindContainereSizeInBytes(unsigned Kind) const;
 
   bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
-                             const MCValue &Target) override;
+                             const MCValue &Target,
+                             const MCSubtargetInfo *STI) override;
 };
 
 } // end anonymous namespace
@@ -499,7 +500,8 @@ bool AArch64AsmBackend::writeNopData(raw_ostream &OS, uint64_t Count,
 
 bool AArch64AsmBackend::shouldForceRelocation(const MCAssembler &Asm,
                                               const MCFixup &Fixup,
-                                              const MCValue &Target) {
+                                              const MCValue &Target,
+                                              const MCSubtargetInfo *STI) {
   unsigned Kind = Fixup.getKind();
   if (Kind >= FirstLiteralRelocationKind)
     return true;
diff --git a/llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUAsmBackend.cpp b/llvm/lib/Target/AMDGPU/MCTargetDesc/AMDGPUAsmBackend.cpp
@@ -53,7 +53,8 @@ class AMDGPUAsmBackend : public MCAsmBackend {
   std::optional<MCFixupKind> getFixupKind(StringRef Name) const override;
   const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const override;
   bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
-                             const MCValue &Target) override;
+                             const MCValue &Target,
+                             const MCSubtargetInfo *STI) override;
 };
 
 } //End anonymous namespace
@@ -192,7 +193,8 @@ const MCFixupKindInfo &AMDGPUAsmBackend::getFixupKindInfo(
 
 bool AMDGPUAsmBackend::shouldForceRelocation(const MCAssembler &,
                                              const MCFixup &Fixup,
-                                             const MCValue &) {
+                                             const MCValue &,
+                                             const MCSubtargetInfo *STI) {
   return Fixup.getKind() >= FirstLiteralRelocationKind;
 }
 
diff --git a/llvm/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp b/llvm/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp
@@ -908,7 +908,8 @@ unsigned ARMAsmBackend::adjustFixupValue(const MCAssembler &Asm,
 
 bool ARMAsmBackend::shouldForceRelocation(const MCAssembler &Asm,
                                           const MCFixup &Fixup,
-                                          const MCValue &Target) {
+                                          const MCValue &Target,
+                                          const MCSubtargetInfo *STI) {
   const MCSymbolRefExpr *A = Target.getSymA();
   const MCSymbol *Sym = A ? &A->getSymbol() : nullptr;
   const unsigned FixupKind = Fixup.getKind();
diff --git a/llvm/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.h b/llvm/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.h
@@ -36,7 +36,8 @@ class ARMAsmBackend : public MCAsmBackend {
   const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const override;
 
   bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
-                             const MCValue &Target) override;
+                             const MCValue &Target,
+                             const MCSubtargetInfo *STI) override;
 
   unsigned adjustFixupValue(const MCAssembler &Asm, const MCFixup &Fixup,
                             const MCValue &Target, uint64_t Value,
diff --git a/llvm/lib/Target/AVR/MCTargetDesc/AVRAsmBackend.cpp b/llvm/lib/Target/AVR/MCTargetDesc/AVRAsmBackend.cpp
@@ -507,7 +507,8 @@ bool AVRAsmBackend::writeNopData(raw_ostream &OS, uint64_t Count,
 
 bool AVRAsmBackend::shouldForceRelocation(const MCAssembler &Asm,
                                           const MCFixup &Fixup,
-                                          const MCValue &Target) {
+                                          const MCValue &Target,
+                                          const MCSubtargetInfo *STI) {
   switch ((unsigned)Fixup.getKind()) {
   default:
     return Fixup.getKind() >= FirstLiteralRelocationKind;
diff --git a/llvm/lib/Target/AVR/MCTargetDesc/AVRAsmBackend.h b/llvm/lib/Target/AVR/MCTargetDesc/AVRAsmBackend.h
@@ -60,7 +60,8 @@ class AVRAsmBackend : public MCAsmBackend {
                     const MCSubtargetInfo *STI) const override;
 
   bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
-                             const MCValue &Target) override;
+                             const MCValue &Target,
+                             const MCSubtargetInfo *STI) override;
 
 private:
   Triple::OSType OSType;
diff --git a/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonAsmBackend.cpp b/llvm/lib/Target/Hexagon/MCTargetDesc/HexagonAsmBackend.cpp
@@ -202,7 +202,8 @@ class HexagonAsmBackend : public MCAsmBackend {
   }
 
   bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
-                             const MCValue &Target) override {
+                             const MCValue &Target,
+                             const MCSubtargetInfo *STI) override {
     switch(Fixup.getTargetKind()) {
       default:
         llvm_unreachable("Unknown Fixup Kind!");
diff --git a/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchAsmBackend.cpp b/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchAsmBackend.cpp
@@ -162,12 +162,13 @@ void LoongArchAsmBackend::applyFixup(const MCAssembler &Asm,
 
 bool LoongArchAsmBackend::shouldForceRelocation(const MCAssembler &Asm,
                                                 const MCFixup &Fixup,
-                                                const MCValue &Target) {
+                                                const MCValue &Target,
+                                                const MCSubtargetInfo *STI) {
   if (Fixup.getKind() >= FirstLiteralRelocationKind)
     return true;
   switch (Fixup.getTargetKind()) {
   default:
-    return STI.hasFeature(LoongArch::FeatureRelax);
+    return STI->hasFeature(LoongArch::FeatureRelax);
   case FK_Data_1:
   case FK_Data_2:
   case FK_Data_4:
diff --git a/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchAsmBackend.h b/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchAsmBackend.h
@@ -41,7 +41,8 @@ class LoongArchAsmBackend : public MCAsmBackend {
                   const MCSubtargetInfo *STI) const override;
 
   bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
-                             const MCValue &Target) override;
+                             const MCValue &Target,
+                             const MCSubtargetInfo *STI) override;
 
   bool fixupNeedsRelaxation(const MCFixup &Fixup, uint64_t Value,
                             const MCRelaxableFragment *DF,
diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp b/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.cpp
@@ -544,7 +544,8 @@ bool MipsAsmBackend::writeNopData(raw_ostream &OS, uint64_t Count,
 
 bool MipsAsmBackend::shouldForceRelocation(const MCAssembler &Asm,
                                            const MCFixup &Fixup,
-                                           const MCValue &Target) {
+                                           const MCValue &Target,
+                                           const MCSubtargetInfo *STI) {
   if (Fixup.getKind() >= FirstLiteralRelocationKind)
     return true;
   const unsigned FixupKind = Fixup.getKind();
diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.h b/llvm/lib/Target/Mips/MCTargetDesc/MipsAsmBackend.h
@@ -68,7 +68,8 @@ class MipsAsmBackend : public MCAsmBackend {
                     const MCSubtargetInfo *STI) const override;
 
   bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
-                             const MCValue &Target) override;
+                             const MCValue &Target,
+                             const MCSubtargetInfo *STI) override;
 
   bool isMicroMips(const MCSymbol *Sym) const override;
 }; // class MipsAsmBackend
diff --git a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCAsmBackend.cpp b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCAsmBackend.cpp
@@ -162,7 +162,8 @@ class PPCAsmBackend : public MCAsmBackend {
   }
 
   bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
-                             const MCValue &Target) override {
+                             const MCValue &Target,
+                             const MCSubtargetInfo *STI) override {
     MCFixupKind Kind = Fixup.getKind();
     switch ((unsigned)Kind) {
     default:
diff --git a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVAsmBackend.cpp b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVAsmBackend.cpp
@@ -108,7 +108,8 @@ RISCVAsmBackend::getFixupKindInfo(MCFixupKind Kind) const {
 // necessary for correctness as offsets may change during relaxation.
 bool RISCVAsmBackend::shouldForceRelocation(const MCAssembler &Asm,
                                             const MCFixup &Fixup,
-                                            const MCValue &Target) {
+                                            const MCValue &Target,
+                                            const MCSubtargetInfo *STI) {
   if (Fixup.getKind() >= FirstLiteralRelocationKind)
     return true;
   switch (Fixup.getTargetKind()) {
@@ -128,7 +129,7 @@ bool RISCVAsmBackend::shouldForceRelocation(const MCAssembler &Asm,
     return true;
   }
 
-  return STI.hasFeature(RISCV::FeatureRelax) || ForceRelocs;
+  return STI->hasFeature(RISCV::FeatureRelax) || ForceRelocs;
 }
 
 bool RISCVAsmBackend::fixupNeedsRelaxationAdvanced(const MCFixup &Fixup,
@@ -514,8 +515,8 @@ static uint64_t adjustFixupValue(const MCFixup &Fixup, uint64_t Value,
 
 bool RISCVAsmBackend::evaluateTargetFixup(
     const MCAssembler &Asm, const MCAsmLayout &Layout, const MCFixup &Fixup,
-    const MCFragment *DF, const MCValue &Target, uint64_t &Value,
-    bool &WasForced) {
+    const MCFragment *DF, const MCValue &Target, const MCSubtargetInfo *STI,
+    uint64_t &Value, bool &WasForced) {
   const MCFixup *AUIPCFixup;
   const MCFragment *AUIPCDF;
   MCValue AUIPCTarget;
@@ -565,7 +566,7 @@ bool RISCVAsmBackend::evaluateTargetFixup(
   Value = Layout.getSymbolOffset(SA) + AUIPCTarget.getConstant();
   Value -= Layout.getFragmentOffset(AUIPCDF) + AUIPCFixup->getOffset();
 
-  if (shouldForceRelocation(Asm, *AUIPCFixup, AUIPCTarget)) {
+  if (shouldForceRelocation(Asm, *AUIPCFixup, AUIPCTarget, STI)) {
     WasForced = true;
     return false;
   }
diff --git a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVAsmBackend.h b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVAsmBackend.h
@@ -50,8 +50,8 @@ class RISCVAsmBackend : public MCAsmBackend {
 
   bool evaluateTargetFixup(const MCAssembler &Asm, const MCAsmLayout &Layout,
                            const MCFixup &Fixup, const MCFragment *DF,
-                           const MCValue &Target, uint64_t &Value,
-                           bool &WasForced) override;
+                           const MCValue &Target, const MCSubtargetInfo *STI,
+                           uint64_t &Value, bool &WasForced) override;
 
   bool handleAddSubRelocations(const MCAsmLayout &Layout, const MCFragment &F,
                                const MCFixup &Fixup, const MCValue &Target,
@@ -66,7 +66,8 @@ class RISCVAsmBackend : public MCAsmBackend {
   createObjectTargetWriter() const override;
 
   bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
-                             const MCValue &Target) override;
+                             const MCValue &Target,
+                             const MCSubtargetInfo *STI) override;
 
   bool fixupNeedsRelaxation(const MCFixup &Fixup, uint64_t Value,
                             const MCRelaxableFragment *DF,
diff --git a/llvm/lib/Target/Sparc/MCTargetDesc/SparcAsmBackend.cpp b/llvm/lib/Target/Sparc/MCTargetDesc/SparcAsmBackend.cpp
@@ -272,7 +272,8 @@ namespace {
     }
 
     bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
-                               const MCValue &Target) override {
+                               const MCValue &Target,
+                               const MCSubtargetInfo *STI) override {
       if (Fixup.getKind() >= FirstLiteralRelocationKind)
         return true;
       switch ((Sparc::Fixups)Fixup.getKind()) {
diff --git a/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZMCAsmBackend.cpp b/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZMCAsmBackend.cpp
@@ -116,7 +116,8 @@ class SystemZMCAsmBackend : public MCAsmBackend {
   std::optional<MCFixupKind> getFixupKind(StringRef Name) const override;
   const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const override;
   bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
-                             const MCValue &Target) override;
+                             const MCValue &Target,
+                             const MCSubtargetInfo *STI) override;
   void applyFixup(const MCAssembler &Asm, const MCFixup &Fixup,
                   const MCValue &Target, MutableArrayRef<char> Data,
                   uint64_t Value, bool IsResolved,
@@ -164,8 +165,9 @@ SystemZMCAsmBackend::getFixupKindInfo(MCFixupKind Kind) const {
 }
 
 bool SystemZMCAsmBackend::shouldForceRelocation(const MCAssembler &,
-						const MCFixup &Fixup,
-						const MCValue &) {
+                                                const MCFixup &Fixup,
+                                                const MCValue &,
+                                                const MCSubtargetInfo *STI) {
   return Fixup.getKind() >= FirstLiteralRelocationKind;
 }
 
diff --git a/llvm/lib/Target/VE/MCTargetDesc/VEAsmBackend.cpp b/llvm/lib/Target/VE/MCTargetDesc/VEAsmBackend.cpp
@@ -132,7 +132,8 @@ class VEAsmBackend : public MCAsmBackend {
   }
 
   bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
-                             const MCValue &Target) override {
+                             const MCValue &Target,
+                             const MCSubtargetInfo *STI) override {
     switch ((VE::Fixups)Fixup.getKind()) {
     default:
       return false;
diff --git a/llvm/lib/Target/X86/MCTargetDesc/X86AsmBackend.cpp b/llvm/lib/Target/X86/MCTargetDesc/X86AsmBackend.cpp
@@ -173,7 +173,8 @@ class X86AsmBackend : public MCAsmBackend {
   const MCFixupKindInfo &getFixupKindInfo(MCFixupKind Kind) const override;
 
   bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,
-                             const MCValue &Target) override;
+                             const MCValue &Target,
+                             const MCSubtargetInfo *STI) override;
 
   void applyFixup(const MCAssembler &Asm, const MCFixup &Fixup,
                   const MCValue &Target, MutableArrayRef<char> Data,
@@ -645,8 +646,8 @@ const MCFixupKindInfo &X86AsmBackend::getFixupKindInfo(MCFixupKind Kind) const {
 }
 
 bool X86AsmBackend::shouldForceRelocation(const MCAssembler &,
-                                          const MCFixup &Fixup,
-                                          const MCValue &) {
+                                          const MCFixup &Fixup, const MCValue &,
+                                          const MCSubtargetInfo *STI) {
   return Fixup.getKind() >= FirstLiteralRelocationKind;
 }
 
diff --git a/llvm/test/CodeGen/RISCV/relax-per-target-feature.ll b/llvm/test/CodeGen/RISCV/relax-per-target-feature.ll
@@ -11,6 +11,7 @@ declare dso_local i32 @ext(i32)
 ; CHECK-NEXT:    c.li a0, 31
 ; CHECK-NEXT:    auipc t1, 0
 ; CHECK-NEXT:    R_RISCV_CALL_PLT     ext
+; CHECK-NEXT:    R_RISCV_RELAX *ABS*
 ; CHECK-NEXT:    jalr zero, 0(t1)
 define dso_local i32 @f() #0 {
 entry:

Original file line number	Diff line number	Diff line change
`@@ -202,7 +202,8 @@ class HexagonAsmBackend : public MCAsmBackend {`
`202`	`202`	`}`
`203`	`203`
`204`	`204`	`bool shouldForceRelocation(const MCAssembler &Asm, const MCFixup &Fixup,`
`205`		`- const MCValue &Target) override {`
	`205`	`+ const MCValue &Target,`
	`206`	`+ const MCSubtargetInfo *STI) override {`
`206`	`207`	`switch(Fixup.getTargetKind()) {`
`207`	`208`	`default:`
`208`	`209`	`llvm_unreachable("Unknown Fixup Kind!");`