diff options
Diffstat (limited to 'llvm/lib/MC/MCSFrame.cpp')
| -rw-r--r-- | llvm/lib/MC/MCSFrame.cpp | 29 |
1 files changed, 24 insertions, 5 deletions
diff --git a/llvm/lib/MC/MCSFrame.cpp b/llvm/lib/MC/MCSFrame.cpp index 066d1a3..910fcab 100644 --- a/llvm/lib/MC/MCSFrame.cpp +++ b/llvm/lib/MC/MCSFrame.cpp @@ -111,6 +111,8 @@ struct SFrameFDE { MCFragment *Frag; // Unwinding fres SmallVector<SFrameFRE> FREs; + // .cfi_remember_state stack + SmallVector<SFrameFRE> SaveState; SFrameFDE(const MCDwarfFrameInfo &DF, MCSymbol *FRES) : DFrame(DF), FREStart(FRES), Frag(nullptr) {} @@ -237,13 +239,30 @@ class SFrameEmitterImpl { case MCCFIInstruction::OpAdjustCfaOffset: return setCFAOffset(FRE, CFI.getLoc(), FRE.CFAOffset + CFI.getOffset()); case MCCFIInstruction::OpRememberState: - // TODO: Implement. Will use FDE. + if (FDE.FREs.size() == 1) { + // Error for gas compatibility: If the initial FRE isn't complete, + // then any state is incomplete. FIXME: Dwarf doesn't error here. + // Why should sframe? + Streamer.getContext().reportWarning( + CFI.getLoc(), "skipping SFrame FDE; .cfi_remember_state without " + "prior SFrame FRE state"); + return false; + } + FDE.SaveState.push_back(FRE); return true; case MCCFIInstruction::OpRestore: - // TODO: Implement. Will use FDE. + // The first FRE generated has the original state. + if (CFI.getRegister() == FPReg) + FRE.FPOffset = FDE.FREs.front().FPOffset; + else if (CFI.getRegister() == RAReg) + FRE.RAOffset = FDE.FREs.front().RAOffset; return true; case MCCFIInstruction::OpRestoreState: - // TODO: Implement. Will use FDE. + // The cfi parser will have caught unbalanced directives earlier, so a + // mismatch here is an implementation error. + assert(!FDE.SaveState.empty() && + "cfi_restore_state without cfi_save_state"); + FRE = FDE.SaveState.pop_back_val(); return true; case MCCFIInstruction::OpEscape: // TODO: Implement. Will use FDE. @@ -394,8 +413,8 @@ public: // shf_fdeoff. With no sfh_auxhdr, these immediately follow this header. Streamer.emitInt32(0); // shf_freoff - Streamer.emitAbsoluteSymbolDiff(FRESubSectionStart, FDESubSectionStart, - sizeof(uint32_t)); + Streamer.emitInt32(FDEs.size() * + sizeof(sframe::FuncDescEntry<endianness::native>)); } void emitFDEs() { |