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[CIR][NFC] Upstream EHPersonality for function (#164883)
Upstream the EHPersonality class for a function as a prerequisite for working with the handlers Issue #154992
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‎clang/lib/CIR/CodeGen/CIRGenCleanup.h‎

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@@ -15,6 +15,7 @@
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#define CLANG_LIB_CIR_CODEGEN_CIRGENCLEANUP_H
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#include "Address.h"
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#include "CIRGenModule.h"
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#include "EHScopeStack.h"
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#include "mlir/IR/Value.h"
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@@ -257,5 +258,53 @@ inline void EHScopeStack::popCatch() {
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deallocate(EHCatchScope::getSizeForNumHandlers(scope.getNumHandlers()));
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}
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/// The exceptions personality for a function.
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struct EHPersonality {
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const char *personalityFn = nullptr;
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// If this is non-null, this personality requires a non-standard
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// function for rethrowing an exception after a catchall cleanup.
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// This function must have prototype void(void*).
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const char *catchallRethrowFn = nullptr;
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static const EHPersonality &get(CIRGenModule &cgm,
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const clang::FunctionDecl *fd);
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static const EHPersonality &get(CIRGenFunction &cgf);
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static const EHPersonality GNU_C;
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static const EHPersonality GNU_C_SJLJ;
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static const EHPersonality GNU_C_SEH;
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static const EHPersonality GNU_ObjC;
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static const EHPersonality GNU_ObjC_SJLJ;
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static const EHPersonality GNU_ObjC_SEH;
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static const EHPersonality GNUstep_ObjC;
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static const EHPersonality GNU_ObjCXX;
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static const EHPersonality NeXT_ObjC;
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static const EHPersonality GNU_CPlusPlus;
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static const EHPersonality GNU_CPlusPlus_SJLJ;
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static const EHPersonality GNU_CPlusPlus_SEH;
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static const EHPersonality MSVC_except_handler;
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static const EHPersonality MSVC_C_specific_handler;
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static const EHPersonality MSVC_CxxFrameHandler3;
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static const EHPersonality GNU_Wasm_CPlusPlus;
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static const EHPersonality XL_CPlusPlus;
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static const EHPersonality ZOS_CPlusPlus;
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/// Does this personality use landingpads or the family of pad instructions
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/// designed to form funclets?
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bool usesFuncletPads() const {
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return isMSVCPersonality() || isWasmPersonality();
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}
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bool isMSVCPersonality() const {
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return this == &MSVC_except_handler || this == &MSVC_C_specific_handler ||
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this == &MSVC_CxxFrameHandler3;
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}
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bool isWasmPersonality() const { return this == &GNU_Wasm_CPlusPlus; }
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bool isMSVCXXPersonality() const { return this == &MSVC_CxxFrameHandler3; }
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};
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} // namespace clang::CIRGen
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#endif // CLANG_LIB_CIR_CODEGEN_CIRGENCLEANUP_H

‎clang/lib/CIR/CodeGen/CIRGenException.cpp‎

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@@ -18,6 +18,171 @@
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using namespace clang;
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using namespace clang::CIRGen;
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const EHPersonality EHPersonality::GNU_C = {"__gcc_personality_v0", nullptr};
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const EHPersonality EHPersonality::GNU_C_SJLJ = {"__gcc_personality_sj0",
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nullptr};
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const EHPersonality EHPersonality::GNU_C_SEH = {"__gcc_personality_seh0",
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nullptr};
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const EHPersonality EHPersonality::NeXT_ObjC = {"__objc_personality_v0",
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nullptr};
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const EHPersonality EHPersonality::GNU_CPlusPlus = {"__gxx_personality_v0",
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nullptr};
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const EHPersonality EHPersonality::GNU_CPlusPlus_SJLJ = {
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"__gxx_personality_sj0", nullptr};
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const EHPersonality EHPersonality::GNU_CPlusPlus_SEH = {
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"__gxx_personality_seh0", nullptr};
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const EHPersonality EHPersonality::GNU_ObjC = {"__gnu_objc_personality_v0",
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"objc_exception_throw"};
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const EHPersonality EHPersonality::GNU_ObjC_SJLJ = {
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"__gnu_objc_personality_sj0", "objc_exception_throw"};
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const EHPersonality EHPersonality::GNU_ObjC_SEH = {
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"__gnu_objc_personality_seh0", "objc_exception_throw"};
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const EHPersonality EHPersonality::GNU_ObjCXX = {
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"__gnustep_objcxx_personality_v0", nullptr};
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const EHPersonality EHPersonality::GNUstep_ObjC = {
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"__gnustep_objc_personality_v0", nullptr};
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const EHPersonality EHPersonality::MSVC_except_handler = {"_except_handler3",
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nullptr};
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const EHPersonality EHPersonality::MSVC_C_specific_handler = {
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"__C_specific_handler", nullptr};
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const EHPersonality EHPersonality::MSVC_CxxFrameHandler3 = {
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"__CxxFrameHandler3", nullptr};
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const EHPersonality EHPersonality::GNU_Wasm_CPlusPlus = {
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"__gxx_wasm_personality_v0", nullptr};
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const EHPersonality EHPersonality::XL_CPlusPlus = {"__xlcxx_personality_v1",
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nullptr};
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const EHPersonality EHPersonality::ZOS_CPlusPlus = {"__zos_cxx_personality_v2",
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nullptr};
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static const EHPersonality &getCPersonality(const TargetInfo &target,
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const CodeGenOptions &cgOpts) {
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const llvm::Triple &triple = target.getTriple();
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if (triple.isWindowsMSVCEnvironment())
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return EHPersonality::MSVC_CxxFrameHandler3;
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if (cgOpts.hasSjLjExceptions())
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return EHPersonality::GNU_C_SJLJ;
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if (cgOpts.hasDWARFExceptions())
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return EHPersonality::GNU_C;
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if (cgOpts.hasSEHExceptions())
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return EHPersonality::GNU_C_SEH;
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return EHPersonality::GNU_C;
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}
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static const EHPersonality &getObjCPersonality(const TargetInfo &target,
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const LangOptions &langOpts,
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const CodeGenOptions &cgOpts) {
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const llvm::Triple &triple = target.getTriple();
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if (triple.isWindowsMSVCEnvironment())
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return EHPersonality::MSVC_CxxFrameHandler3;
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switch (langOpts.ObjCRuntime.getKind()) {
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case ObjCRuntime::FragileMacOSX:
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return getCPersonality(target, cgOpts);
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case ObjCRuntime::MacOSX:
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case ObjCRuntime::iOS:
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case ObjCRuntime::WatchOS:
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return EHPersonality::NeXT_ObjC;
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case ObjCRuntime::GNUstep:
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if (langOpts.ObjCRuntime.getVersion() >= VersionTuple(1, 7))
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return EHPersonality::GNUstep_ObjC;
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[[fallthrough]];
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case ObjCRuntime::GCC:
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case ObjCRuntime::ObjFW:
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if (cgOpts.hasSjLjExceptions())
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return EHPersonality::GNU_ObjC_SJLJ;
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if (cgOpts.hasSEHExceptions())
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return EHPersonality::GNU_ObjC_SEH;
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return EHPersonality::GNU_ObjC;
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}
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llvm_unreachable("bad runtime kind");
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}
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static const EHPersonality &getCXXPersonality(const TargetInfo &target,
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const CodeGenOptions &cgOpts) {
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const llvm::Triple &triple = target.getTriple();
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if (triple.isWindowsMSVCEnvironment())
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return EHPersonality::MSVC_CxxFrameHandler3;
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if (triple.isOSAIX())
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return EHPersonality::XL_CPlusPlus;
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if (cgOpts.hasSjLjExceptions())
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return EHPersonality::GNU_CPlusPlus_SJLJ;
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if (cgOpts.hasDWARFExceptions())
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return EHPersonality::GNU_CPlusPlus;
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if (cgOpts.hasSEHExceptions())
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return EHPersonality::GNU_CPlusPlus_SEH;
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if (cgOpts.hasWasmExceptions())
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return EHPersonality::GNU_Wasm_CPlusPlus;
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return EHPersonality::GNU_CPlusPlus;
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}
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/// Determines the personality function to use when both C++
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/// and Objective-C exceptions are being caught.
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static const EHPersonality &getObjCXXPersonality(const TargetInfo &target,
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const LangOptions &langOpts,
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const CodeGenOptions &cgOpts) {
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if (target.getTriple().isWindowsMSVCEnvironment())
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return EHPersonality::MSVC_CxxFrameHandler3;
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switch (langOpts.ObjCRuntime.getKind()) {
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// In the fragile ABI, just use C++ exception handling and hope
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// they're not doing crazy exception mixing.
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case ObjCRuntime::FragileMacOSX:
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return getCXXPersonality(target, cgOpts);
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// The ObjC personality defers to the C++ personality for non-ObjC
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// handlers. Unlike the C++ case, we use the same personality
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// function on targets using (backend-driven) SJLJ EH.
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case ObjCRuntime::MacOSX:
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case ObjCRuntime::iOS:
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case ObjCRuntime::WatchOS:
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return getObjCPersonality(target, langOpts, cgOpts);
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case ObjCRuntime::GNUstep:
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return EHPersonality::GNU_ObjCXX;
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// The GCC runtime's personality function inherently doesn't support
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// mixed EH. Use the ObjC personality just to avoid returning null.
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case ObjCRuntime::GCC:
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case ObjCRuntime::ObjFW:
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return getObjCPersonality(target, langOpts, cgOpts);
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}
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llvm_unreachable("bad runtime kind");
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}
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static const EHPersonality &getSEHPersonalityMSVC(const llvm::Triple &triple) {
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return triple.getArch() == llvm::Triple::x86
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? EHPersonality::MSVC_except_handler
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: EHPersonality::MSVC_C_specific_handler;
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}
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const EHPersonality &EHPersonality::get(CIRGenModule &cgm,
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const FunctionDecl *fd) {
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const llvm::Triple &triple = cgm.getTarget().getTriple();
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const LangOptions &langOpts = cgm.getLangOpts();
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const CodeGenOptions &cgOpts = cgm.getCodeGenOpts();
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const TargetInfo &target = cgm.getTarget();
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// Functions using SEH get an SEH personality.
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if (fd && fd->usesSEHTry())
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return getSEHPersonalityMSVC(triple);
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if (langOpts.ObjC) {
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return langOpts.CPlusPlus ? getObjCXXPersonality(target, langOpts, cgOpts)
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: getObjCPersonality(target, langOpts, cgOpts);
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}
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return langOpts.CPlusPlus ? getCXXPersonality(target, cgOpts)
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: getCPersonality(target, cgOpts);
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}
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const EHPersonality &EHPersonality::get(CIRGenFunction &cgf) {
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const auto *fg = cgf.curCodeDecl;
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// For outlined finallys and filters, use the SEH personality in case they
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// contain more SEH. This mostly only affects finallys. Filters could
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// hypothetically use gnu statement expressions to sneak in nested SEH.
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fg = fg ? fg : cgf.curSEHParent.getDecl();
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return get(cgf.cgm, dyn_cast_or_null<FunctionDecl>(fg));
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}
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void CIRGenFunction::emitCXXThrowExpr(const CXXThrowExpr *e) {
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const llvm::Triple &triple = getTarget().getTriple();
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if (cgm.getLangOpts().OpenMPIsTargetDevice &&

‎clang/lib/CIR/CodeGen/CIRGenFunction.h‎

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/// Tracks function scope overall cleanup handling.
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EHScopeStack ehStack;
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GlobalDecl curSEHParent;
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llvm::DenseMap<const clang::ValueDecl *, clang::FieldDecl *>
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lambdaCaptureFields;
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clang::FieldDecl *lambdaThisCaptureField = nullptr;

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