Index: lib/MC/MCWin64EH.cpp =================================================================== --- lib/MC/MCWin64EH.cpp +++ lib/MC/MCWin64EH.cpp @@ -453,6 +453,37 @@ } } +// Returns true if an epilog with the exact same unwind code sequence exists. +// EpilogInstrs - Unwind codes for the current epilog. +// Epilogs - Epilogs that potentialy match the current epilog. +static std::pair +FindMatchingEpilog(const std::vector& EpilogInstrs, + const std::vector& Epilogs, + const WinEH::FrameInfo *info) { + for (auto *EpilogStart : Epilogs) { + auto InstrsIter = info->EpilogMap.find(EpilogStart); + assert(InstrsIter != info->EpilogMap.end() && + "Epilog not found in EpilogMap"); + const auto &Instrs = InstrsIter->second; + unsigned NumMatchingInstrs = 0; + + assert(Instrs.size() == EpilogInstrs.size() && + "Number of unwind codes does not match"); + + for (int i = 0; i < Instrs.size(); ++i) { + if (Instrs[i].Operation != EpilogInstrs[i].Operation || + Instrs[i].Offset != EpilogInstrs[i].Offset || + Instrs[i].Register != EpilogInstrs[i].Register) + break; + ++NumMatchingInstrs; + } + + if (NumMatchingInstrs == EpilogInstrs.size()) + return std::make_pair(true, EpilogStart); + } + return std::make_pair(false, nullptr); +} + // Populate the .xdata section. The format of .xdata on ARM64 is documented at // https://docs.microsoft.com/en-us/cpp/build/arm64-exception-handling static void ARM64EmitUnwindInfo(MCStreamer &streamer, WinEH::FrameInfo *info) { @@ -477,12 +508,30 @@ // Process epilogs. MapVector EpilogInfo; + // Epilogs processed so far, indexed by the number of unwind codes and the total + // size of the unwind codes. + DenseMap>> AddedEpilogs; + for (auto &I : info->EpilogMap) { MCSymbol *EpilogStart = I.first; auto &EpilogInstrs = I.second; uint32_t CodeBytes = ARM64CountOfUnwindCodes(EpilogInstrs); - EpilogInfo[EpilogStart] = TotalCodeBytes; - TotalCodeBytes += CodeBytes; + + uint32_t NumUnwindCodes = EpilogInstrs.size(); + auto &Epilogs = AddedEpilogs[NumUnwindCodes][CodeBytes]; + + std::pair MatchingEpilog = + FindMatchingEpilog(EpilogInstrs, Epilogs, info); + if (MatchingEpilog.first) { + assert(EpilogInfo.find(MatchingEpilog.second) != EpilogInfo.end() && + "Duplicate epilog not found"); + EpilogInfo[EpilogStart] = EpilogInfo[MatchingEpilog.second]; + EpilogInstrs.clear(); + } else { + EpilogInfo[EpilogStart] = TotalCodeBytes; + TotalCodeBytes += CodeBytes; + Epilogs.push_back(EpilogStart); + } } // Code Words, Epilog count, E, X, Vers, Function Length Index: test/CodeGen/AArch64/wineh4.mir =================================================================== --- test/CodeGen/AArch64/wineh4.mir +++ test/CodeGen/AArch64/wineh4.mir @@ -1,7 +1,7 @@ # RUN: llc -o - %s -mtriple=aarch64-windows -start-after=prologepilog \ # RUN: -disable-branch-fold -filetype=obj \ # RUN: | llvm-readobj -unwind | FileCheck %s -# Check that multiple epilgoues are correctly placed in .xdata. +# Check that identical multiple epilgoues are correctly shared in .xdata. # CHECK: ExceptionData { # CHECK-NEXT: FunctionLength: 164 @@ -9,7 +9,7 @@ # CHECK-NEXT: ExceptionData: No # CHECK-NEXT: EpiloguePacked: No # CHECK-NEXT: EpilogueScopes: 2 -# CHECK-NEXT: ByteCodeLength: 48 +# CHECK-NEXT: ByteCodeLength: 32 # CHECK-NEXT: Prologue [ # CHECK-NEXT: 0xc80c ; stp x19, x20, [sp, #96] # CHECK-NEXT: 0xc88a ; stp x21, x22, [sp, #80] @@ -37,7 +37,7 @@ # CHECK-NEXT: } # CHECK-NEXT: EpilogueScope { # CHECK-NEXT: StartOffset: 33 -# CHECK-NEXT: EpilogueStartIndex: 30 +# CHECK-NEXT: EpilogueStartIndex: 15 # CHECK-NEXT: Opcodes [ # CHECK-NEXT: 0xc80c ; ldp x19, x20, [sp, #96] # CHECK-NEXT: 0xc88a ; ldp x21, x22, [sp, #80] Index: test/CodeGen/AArch64/wineh8.mir =================================================================== --- /dev/null +++ test/CodeGen/AArch64/wineh8.mir @@ -0,0 +1,225 @@ +# RUN: llc -o - %s -mtriple=aarch64-windows -start-after=prologepilog \ +# RUN: -disable-branch-fold -filetype=obj \ +# RUN: | llvm-readobj -unwind | FileCheck %s +# Check that non-identical multiple epilgoues are correctly shared in .xdata. + +# CHECK: ExceptionData { +# CHECK-NEXT: FunctionLength: 160 +# CHECK-NEXT: Version: 0 +# CHECK-NEXT: ExceptionData: No +# CHECK-NEXT: EpiloguePacked: No +# CHECK-NEXT: EpilogueScopes: 2 +# CHECK-NEXT: ByteCodeLength: 44 +# CHECK-NEXT: Prologue [ +# CHECK-NEXT: 0xc80c ; stp x19, x20, [sp, #96] +# CHECK-NEXT: 0xc88a ; stp x21, x22, [sp, #80] +# CHECK-NEXT: 0xc908 ; stp x23, x24, [sp, #64] +# CHECK-NEXT: 0xc986 ; stp x25, x26, [sp, #48] +# CHECK-NEXT: 0xca04 ; stp x27, x28, [sp, #32] +# CHECK-NEXT: 0xd802 ; stp d8, d9, [sp, #16] +# CHECK-NEXT: 0xda8d ; stp d10, d11, [sp, #-112]! +# CHECK-NEXT: 0xe4 ; end +# CHECK-NEXT: ] +# CHECK-NEXT: EpilogueScopes [ +# CHECK-NEXT: EpilogueScope { +# CHECK-NEXT: StartOffset: 16 +# CHECK-NEXT: EpilogueStartIndex: 15 +# CHECK-NEXT: Opcodes [ +# CHECK-NEXT: 0xc80c ; ldp x19, x20, [sp, #96] +# CHECK-NEXT: 0xc88a ; ldp x21, x22, [sp, #80] +# CHECK-NEXT: 0xc908 ; ldp x23, x24, [sp, #64] +# CHECK-NEXT: 0xc986 ; ldp x25, x26, [sp, #48] +# CHECK-NEXT: 0xd802 ; ldp d8, d9, [sp, #16] +# CHECK-NEXT: 0xda8d ; ldp d10, d11, [sp], #112 +# CHECK-NEXT: 0xe4 ; end +# CHECK-NEXT: ] +# CHECK-NEXT: } +# CHECK-NEXT: EpilogueScope { +# CHECK-NEXT: StartOffset: 32 +# CHECK-NEXT: EpilogueStartIndex: 28 +# CHECK-NEXT: Opcodes [ +# CHECK-NEXT: 0xc80c ; ldp x19, x20, [sp, #96] +# CHECK-NEXT: 0xc88a ; ldp x21, x22, [sp, #80] +# CHECK-NEXT: 0xc908 ; ldp x23, x24, [sp, #64] +# CHECK-NEXT: 0xc986 ; ldp x25, x26, [sp, #48] +# CHECK-NEXT: 0xca04 ; ldp x27, x28, [sp, #32] +# CHECK-NEXT: 0xd802 ; ldp d8, d9, [sp, #16] +# CHECK-NEXT: 0xda8d ; ldp d10, d11, [sp], #112 +# CHECK-NEXT: 0xe4 ; end +# CHECK-NEXT: ] +# CHECK-NEXT: } +# CHECK-NEXT: ] +# CHECK-NEXT: } +... +--- +name: test +alignment: 2 +exposesReturnsTwice: false +legalized: false +regBankSelected: false +selected: false +failedISel: false +tracksRegLiveness: true +hasWinCFI: true +registers: +liveins: + - { reg: '$w0', virtual-reg: '' } +frameInfo: + isFrameAddressTaken: false + isReturnAddressTaken: false + hasStackMap: false + hasPatchPoint: false + stackSize: 112 + offsetAdjustment: 0 + maxAlignment: 8 + adjustsStack: false + hasCalls: false + stackProtector: '' + maxCallFrameSize: 0 + hasOpaqueSPAdjustment: true + hasVAStart: false + hasMustTailInVarArgFunc: false + localFrameSize: 0 + savePoint: '' + restorePoint: '' +fixedStack: +stack: + - { id: 0, name: '', type: spill-slot, offset: -8, size: 8, alignment: 8, + stack-id: 0, callee-saved-register: '$x19', callee-saved-restored: true, + debug-info-variable: '', debug-info-expression: '', debug-info-location: '' } + - { id: 1, name: '', type: spill-slot, offset: -16, size: 8, alignment: 8, + stack-id: 0, callee-saved-register: '$x20', callee-saved-restored: true, + debug-info-variable: '', debug-info-expression: '', debug-info-location: '' } + - { id: 2, name: '', type: spill-slot, offset: -24, size: 8, alignment: 8, + stack-id: 0, callee-saved-register: '$x21', callee-saved-restored: true, + debug-info-variable: '', debug-info-expression: '', debug-info-location: '' } + - { id: 3, name: '', type: spill-slot, offset: -32, size: 8, alignment: 8, + stack-id: 0, callee-saved-register: '$x22', callee-saved-restored: true, + debug-info-variable: '', debug-info-expression: '', debug-info-location: '' } + - { id: 4, name: '', type: spill-slot, offset: -40, size: 8, alignment: 8, + stack-id: 0, callee-saved-register: '$x23', callee-saved-restored: true, + debug-info-variable: '', debug-info-expression: '', debug-info-location: '' } + - { id: 5, name: '', type: spill-slot, offset: -48, size: 8, alignment: 8, + stack-id: 0, callee-saved-register: '$x24', callee-saved-restored: true, + debug-info-variable: '', debug-info-expression: '', debug-info-location: '' } + - { id: 6, name: '', type: spill-slot, offset: -56, size: 8, alignment: 8, + stack-id: 0, callee-saved-register: '$x25', callee-saved-restored: true, + debug-info-variable: '', debug-info-expression: '', debug-info-location: '' } + - { id: 7, name: '', type: spill-slot, offset: -64, size: 8, alignment: 8, + stack-id: 0, callee-saved-register: '$x26', callee-saved-restored: true, + debug-info-variable: '', debug-info-expression: '', debug-info-location: '' } + - { id: 8, name: '', type: spill-slot, offset: -72, size: 8, alignment: 8, + stack-id: 0, callee-saved-register: '$x27', callee-saved-restored: true, + debug-info-variable: '', debug-info-expression: '', debug-info-location: '' } + - { id: 9, name: '', type: spill-slot, offset: -80, size: 8, alignment: 8, + stack-id: 0, callee-saved-register: '$x28', callee-saved-restored: true, + debug-info-variable: '', debug-info-expression: '', debug-info-location: '' } + - { id: 10, name: '', type: spill-slot, offset: -88, size: 8, alignment: 8, + stack-id: 0, callee-saved-register: '$d8', callee-saved-restored: true, + debug-info-variable: '', debug-info-expression: '', debug-info-location: '' } + - { id: 11, name: '', type: spill-slot, offset: -96, size: 8, alignment: 8, + stack-id: 0, callee-saved-register: '$d9', callee-saved-restored: true, + debug-info-variable: '', debug-info-expression: '', debug-info-location: '' } + - { id: 12, name: '', type: spill-slot, offset: -104, size: 8, alignment: 8, + stack-id: 0, callee-saved-register: '$d10', callee-saved-restored: true, + debug-info-variable: '', debug-info-expression: '', debug-info-location: '' } + - { id: 13, name: '', type: spill-slot, offset: -112, size: 8, alignment: 8, + stack-id: 0, callee-saved-register: '$d11', callee-saved-restored: true, + debug-info-variable: '', debug-info-expression: '', debug-info-location: '' } +constants: +body: | + bb.0.entry: + successors: %bb.2(0x40000000), %bb.1(0x40000000) + liveins: $x0, $x1, $d0, $d1, $d10, $d11, $d8, $d9, $x27, $x28, $x25, $x26, $x23, $x24, $x21, $x22, $x19, $x20 + + early-clobber $sp = frame-setup STPDpre killed $d10, killed $d11, $sp, -14 :: (store 8 into %stack.12), (store 8 into %stack.13) + frame-setup SEH_SaveFRegP_X 10, 11, -112 + frame-setup STPDi killed $d8, killed $d9, $sp, 2 :: (store 8 into %stack.10), (store 8 into %stack.11) + frame-setup SEH_SaveFRegP 8, 9, 16 + frame-setup STPXi killed $x27, killed $x28, $sp, 4 :: (store 8 into %stack.8), (store 8 into %stack.9) + frame-setup SEH_SaveRegP 27, 28, 32 + frame-setup STPXi killed $x25, killed $x26, $sp, 6 :: (store 8 into %stack.6), (store 8 into %stack.7) + frame-setup SEH_SaveRegP 25, 26, 48 + frame-setup STPXi killed $x23, killed $x24, $sp, 8 :: (store 8 into %stack.4), (store 8 into %stack.5) + frame-setup SEH_SaveRegP 23, 24, 64 + frame-setup STPXi killed $x21, killed $x22, $sp, 10 :: (store 8 into %stack.2), (store 8 into %stack.3) + frame-setup SEH_SaveRegP 21, 22, 80 + frame-setup STPXi killed $x19, killed $x20, $sp, 12 :: (store 8 into %stack.0), (store 8 into %stack.1) + frame-setup SEH_SaveRegP 19, 20, 96 + frame-setup SEH_PrologEnd + frame-setup CFI_INSTRUCTION def_cfa_offset 112 + frame-setup CFI_INSTRUCTION offset $w19, -8 + frame-setup CFI_INSTRUCTION offset $w20, -16 + frame-setup CFI_INSTRUCTION offset $w21, -24 + frame-setup CFI_INSTRUCTION offset $w22, -32 + frame-setup CFI_INSTRUCTION offset $w23, -40 + frame-setup CFI_INSTRUCTION offset $w24, -48 + frame-setup CFI_INSTRUCTION offset $w25, -56 + frame-setup CFI_INSTRUCTION offset $w26, -64 + frame-setup CFI_INSTRUCTION offset $w27, -72 + frame-setup CFI_INSTRUCTION offset $w28, -80 + frame-setup CFI_INSTRUCTION offset $b8, -88 + frame-setup CFI_INSTRUCTION offset $b9, -96 + frame-setup CFI_INSTRUCTION offset $b10, -104 + frame-setup CFI_INSTRUCTION offset $b11, -112 + $x19 = ADDXrr $x0, killed $x1 + $d8 = FADDDrr killed $d0, $d1 + $d9 = FADDDrr $d8, $d1 + $d10 = FADDDrr $d9, $d8 + $d11 = FADDDrr killed $d9, $d10 + $x20 = SUBSXrr $x19, killed $x0, implicit-def $nzcv + Bcc 1, %bb.2, implicit killed $nzcv + B %bb.1 + + bb.1: + liveins: $x19, $x20 + + $x21 = ADDXrr $x20, killed $x19 + $x22 = ADDXrr $x21, killed $x20 + $x23 = ADDXrr $x22, killed $x21 + $x24 = ADDXrr $x23, killed $x22 + $x25 = ADDXrr $x24, killed $x23 + $x26 = ADDXrr $x25, killed $x24 + $x27 = ADDXrr $x26, killed $x25 + $x28 = ADDXrr $x27, killed $x26 + $x0 = COPY $x28 + frame-destroy SEH_EpilogStart + $x19, $x20 = frame-destroy LDPXi $sp, 12 :: (load 8 from %stack.0), (load 8 from %stack.1) + frame-destroy SEH_SaveRegP 19, 20, 96 + $x21, $x22 = frame-destroy LDPXi $sp, 10 :: (load 8 from %stack.2), (load 8 from %stack.3) + frame-destroy SEH_SaveRegP 21, 22, 80 + $x23, $x24 = frame-destroy LDPXi $sp, 8 :: (load 8 from %stack.4), (load 8 from %stack.5) + frame-destroy SEH_SaveRegP 23, 24, 64 + $x25, $x26 = frame-destroy LDPXi $sp, 6 :: (load 8 from %stack.6), (load 8 from %stack.7) + frame-destroy SEH_SaveRegP 25, 26, 48 + $x27, $x28 = frame-destroy LDPXi $sp, 4 :: (load 8 from %stack.8), (load 8 from %stack.9) + frame-destroy SEH_SaveRegP 27, 28, 32 + $d8, $d9 = frame-destroy LDPDi $sp, 2 :: (load 8 from %stack.10), (load 8 from %stack.11) + frame-destroy SEH_SaveFRegP 8, 9, 16 + early-clobber $sp, $d10, $d11 = frame-destroy LDPDpost $sp, 14 :: (load 8 from %stack.12), (load 8 from %stack.13) + frame-destroy SEH_SaveFRegP_X 10, 11, -112 + frame-destroy SEH_EpilogEnd + RET_ReallyLR implicit $x0 + + bb.2: + liveins: $x28, $d11 + + $x0 = COPY $d11 + $x0 = ADDXrr $x0, killed $x28 + frame-destroy SEH_EpilogStart + $x19, $x20 = frame-destroy LDPXi $sp, 12 :: (load 8 from %stack.0), (load 8 from %stack.1) + frame-destroy SEH_SaveRegP 19, 20, 96 + $x21, $x22 = frame-destroy LDPXi $sp, 10 :: (load 8 from %stack.2), (load 8 from %stack.3) + frame-destroy SEH_SaveRegP 21, 22, 80 + $x23, $x24 = frame-destroy LDPXi $sp, 8 :: (load 8 from %stack.4), (load 8 from %stack.5) + frame-destroy SEH_SaveRegP 23, 24, 64 + $x25, $x26 = frame-destroy LDPXi $sp, 6 :: (load 8 from %stack.6), (load 8 from %stack.7) + frame-destroy SEH_SaveRegP 25, 26, 48 + $d8, $d9 = frame-destroy LDPDi $sp, 2 :: (load 8 from %stack.10), (load 8 from %stack.11) + frame-destroy SEH_SaveFRegP 8, 9, 16 + early-clobber $sp, $d10, $d11 = frame-destroy LDPDpost $sp, 14 :: (load 8 from %stack.12), (load 8 from %stack.13) + frame-destroy SEH_SaveFRegP_X 10, 11, -112 + frame-destroy SEH_EpilogEnd + RET_ReallyLR implicit $x0 + +...