From 05d340bbd1f6ecba7e8f37037498e9ef80117db6 Mon Sep 17 00:00:00 2001 From: Duncan Sands Date: Mon, 21 May 2007 18:50:28 +0000 Subject: [PATCH] Only emit one entry in the exception action table for each action, even if it occurs for multiple landing pads. llvm-svn: 37267 --- lib/CodeGen/DwarfWriter.cpp | 183 +++++++++++++++++++++++------------- 1 file changed, 117 insertions(+), 66 deletions(-) diff --git a/lib/CodeGen/DwarfWriter.cpp b/lib/CodeGen/DwarfWriter.cpp index 54ccc3b1cfc..7076190c3d2 100644 --- a/lib/CodeGen/DwarfWriter.cpp +++ b/lib/CodeGen/DwarfWriter.cpp @@ -2893,7 +2893,46 @@ private: if (const char *UsedDirective = TAI->getUsedDirective()) O << UsedDirective << EHFrameInfo.FnName << ".eh\n\n"; } - + + /// EquivPads - Whether two landing pads have equivalent actions. + static bool EquivPads(const LandingPadInfo *L, const LandingPadInfo *R) { + const std::vector &LIds = L->TypeIds; + const std::vector &RIds = R->TypeIds; + unsigned LSize = LIds.size(), RSize = RIds.size(); + + if (L->IsFilter != R->IsFilter) + return false; + + if (LSize != RSize) + return false; + + for (unsigned i = 0; i != LSize; ++i) + if (LIds[i] != RIds[i]) + return false; + + return true; + } + + /// PadLT - An order on landing pads, with EquivPads as order equivalence. + static bool PadLT(const LandingPadInfo *L, const LandingPadInfo *R) { + const std::vector &LIds = L->TypeIds; + const std::vector &RIds = R->TypeIds; + unsigned LSize = LIds.size(), RSize = RIds.size(); + + if (L->IsFilter != R->IsFilter) + // Make filters come last + return L->IsFilter < R->IsFilter; + + if (LSize != RSize) + return LSize < RSize; + + for (unsigned i = 0; i != LSize; ++i) + if (LIds[i] != RIds[i]) + return LIds[i] < RIds[i]; + + return false; // Equivalent + } + /// EmitExceptionTable - Emit landpads and actions. /// /// The general organization of the table is complex, but the basic concepts @@ -2931,16 +2970,21 @@ private: void EmitExceptionTable() { // Map all labels and get rid of any dead landing pads. MMI->TidyLandingPads(); - + const std::vector &TypeInfos = MMI->getTypeInfos(); - const std::vector &LandingPads = MMI->getLandingPads(); - if (LandingPads.empty()) return; - - // FIXME - Should fold actions for multiple landing pads. - + const std::vector &PadInfos = MMI->getLandingPads(); + if (PadInfos.empty()) return; + + // Sort the landing pads in order of their type ids. This is used to fold + // duplicate actions. + SmallVector LandingPads(PadInfos.size(), NULL); + for (unsigned i = 0, N = PadInfos.size(); i != N; ++i) + LandingPads[i] = &PadInfos[i]; + std::sort(LandingPads.begin(), LandingPads.end(), PadLT); + // Gather first action index for each landing pad site. - SmallVector Actions; - + SmallVector Actions; + // FIXME - Assume there is only one filter typeinfo list per function // time being. I.E., Each call to eh_filter will have the same list. // This can change if a function is inlined. @@ -2952,43 +2996,47 @@ private: // Look at each landing pad site to compute size. We need the size of each // landing pad site info and the size of the landing pad's actions. - for (unsigned i = 0, N = LandingPads.size(); i != N; ++i) { - const LandingPadInfo &LandingPad = LandingPads[i]; - bool IsFilter = LandingPad.IsFilter; - unsigned SizeSiteActions = 0; - const std::vector &TypeIds = LandingPad.TypeIds; - unsigned SizeAction = 0; - signed FirstAction; + signed FirstAction; - if (IsFilter) { - // FIXME - Assume there is only one filter typeinfo list per function - // time being. I.E., Each call to eh_filter will have the same list. - // This can change if a function is inlined. - Filter = &LandingPad; - SizeAction = Asm->SizeSLEB128(-1) + Asm->SizeSLEB128(0); - SizeSiteActions += SizeAction; - // Record the first action of the landing pad site. - FirstAction = SizeActions + SizeSiteActions - SizeAction + 1; - } else if (TypeIds.empty()) { - FirstAction = 0; - } else { - // Gather the action sizes - for (unsigned j = 0, M = TypeIds.size(); j != M; ++j) { - unsigned TypeID = TypeIds[j]; - unsigned SizeTypeID = Asm->SizeSLEB128(TypeID); - signed Action = j ? -(SizeAction + SizeTypeID) : 0; - SizeAction = SizeTypeID + Asm->SizeSLEB128(Action); + for (unsigned i = 0, N = LandingPads.size(); i != N; ++i) { + const LandingPadInfo *LandingPad = LandingPads[i]; + unsigned SizeSiteActions = 0; + + if (!i || !EquivPads(LandingPad, LandingPads[i-1])) { + const std::vector &TypeIds = LandingPad->TypeIds; + unsigned SizeAction = 0; + + if (LandingPad->IsFilter) { + // FIXME - Assume there is only one filter typeinfo list per function + // time being. I.E., Each call to eh_filter will have the same list. + // This can change if a function is inlined. + Filter = LandingPad; + SizeAction = Asm->SizeSLEB128(-1) + Asm->SizeSLEB128(0); SizeSiteActions += SizeAction; + // Record the first action of the landing pad site. + FirstAction = SizeActions + SizeSiteActions - SizeAction + 1; + } else if (TypeIds.empty()) { + FirstAction = 0; + } else { + // Gather the action sizes + for (unsigned j = 0, M = TypeIds.size(); j != M; ++j) { + unsigned TypeID = TypeIds[j]; + unsigned SizeTypeID = Asm->SizeSLEB128(TypeID); + signed Action = j ? -(SizeAction + SizeTypeID) : 0; + SizeAction = SizeTypeID + Asm->SizeSLEB128(Action); + SizeSiteActions += SizeAction; + } + + // Record the first action of the landing pad site. + FirstAction = SizeActions + SizeSiteActions - SizeAction + 1; } - - // Record the first action of the landing pad site. - FirstAction = SizeActions + SizeSiteActions - SizeAction + 1; - } + } // else re-use previous FirstAction + Actions.push_back(FirstAction); - + // Compute this sites contribution to size. SizeActions += SizeSiteActions; - unsigned M = LandingPad.BeginLabels.size(); + unsigned M = LandingPad->BeginLabels.size(); SizeSites += M*(sizeof(int32_t) + // Site start. sizeof(int32_t) + // Site length. sizeof(int32_t) + // Landing pad. @@ -3035,9 +3083,9 @@ private: PadMapType PadMap; for (unsigned i = 0, N = LandingPads.size(); i != N; ++i) { - const LandingPadInfo &LandingPad = LandingPads[i]; - for (unsigned j=0, E = LandingPad.BeginLabels.size(); j != E; ++j) { - unsigned BeginLabel = LandingPad.BeginLabels[j]; + const LandingPadInfo *LandingPad = LandingPads[i]; + for (unsigned j=0, E = LandingPad->BeginLabels.size(); j != E; ++j) { + unsigned BeginLabel = LandingPad->BeginLabels[j]; assert(!PadMap.count(BeginLabel) && "duplicate landing pad labels!"); PadSite P = { i, j }; PadMap[BeginLabel] = P; @@ -3058,27 +3106,28 @@ private: continue; PadSite P = L->second; - const LandingPadInfo &LandingPad = LandingPads[P.PadIndex]; + const LandingPadInfo *LandingPad = LandingPads[P.PadIndex]; - assert(BeginLabel == LandingPad.BeginLabels[P.SiteIndex] && + assert(BeginLabel == LandingPad->BeginLabels[P.SiteIndex] && "Inconsistent landing pad map!"); EmitSectionOffset("label", "eh_func_begin", BeginLabel, SubprogramCount, false, true); Asm->EOL("Region start"); - EmitDifference("label", LandingPad.EndLabels[P.SiteIndex], + EmitDifference("label", LandingPad->EndLabels[P.SiteIndex], "label", BeginLabel); Asm->EOL("Region length"); - if (LandingPad.TypeIds.empty()) { + if (LandingPad->TypeIds.empty()) { if (TAI->getAddressSize() == sizeof(int32_t)) Asm->EmitInt32(0); else Asm->EmitInt64(0); } else { - EmitSectionOffset("label", "eh_func_begin", LandingPad.LandingPadLabel, - SubprogramCount, false, true); + EmitSectionOffset("label", "eh_func_begin", + LandingPad->LandingPadLabel, SubprogramCount, + false, true); } Asm->EOL("Landing pad"); @@ -3089,25 +3138,27 @@ private: // Emit the actions. for (unsigned i = 0, N = LandingPads.size(); i != N; ++i) { - const LandingPadInfo &LandingPad = LandingPads[i]; - const std::vector &TypeIds = LandingPad.TypeIds; - unsigned SizeAction = 0; - - if (LandingPad.IsFilter) { - Asm->EmitSLEB128Bytes(-1); - Asm->EOL("TypeInfo index"); - Asm->EmitSLEB128Bytes(0); - Asm->EOL("Next action"); - } else { - for (unsigned j = 0, M = TypeIds.size(); j < M; ++j) { - unsigned TypeID = TypeIds[j]; - unsigned SizeTypeID = Asm->SizeSLEB128(TypeID); - Asm->EmitSLEB128Bytes(TypeID); + if (!i || Actions[i] != Actions[i-1]) { + const LandingPadInfo *LandingPad = LandingPads[i]; + const std::vector &TypeIds = LandingPad->TypeIds; + unsigned SizeAction = 0; + + if (LandingPad->IsFilter) { + Asm->EmitSLEB128Bytes(-1); Asm->EOL("TypeInfo index"); - signed Action = j ? -(SizeAction + SizeTypeID) : 0; - SizeAction = SizeTypeID + Asm->SizeSLEB128(Action); - Asm->EmitSLEB128Bytes(Action); + Asm->EmitSLEB128Bytes(0); Asm->EOL("Next action"); + } else { + for (unsigned j = 0, M = TypeIds.size(); j < M; ++j) { + unsigned TypeID = TypeIds[j]; + unsigned SizeTypeID = Asm->SizeSLEB128(TypeID); + Asm->EmitSLEB128Bytes(TypeID); + Asm->EOL("TypeInfo index"); + signed Action = j ? -(SizeAction + SizeTypeID) : 0; + SizeAction = SizeTypeID + Asm->SizeSLEB128(Action); + Asm->EmitSLEB128Bytes(Action); + Asm->EOL("Next action"); + } } } }