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-rw-r--r--llvm/lib/Target/ARM/ARMTargetObjectFile.cpp99
1 files changed, 99 insertions, 0 deletions
diff --git a/llvm/lib/Target/ARM/ARMTargetObjectFile.cpp b/llvm/lib/Target/ARM/ARMTargetObjectFile.cpp
new file mode 100644
index 000000000000..891329d3f297
--- /dev/null
+++ b/llvm/lib/Target/ARM/ARMTargetObjectFile.cpp
@@ -0,0 +1,99 @@
+//===-- llvm/Target/ARMTargetObjectFile.cpp - ARM Object Info Impl --------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "ARMTargetObjectFile.h"
+#include "ARMSubtarget.h"
+#include "ARMTargetMachine.h"
+#include "llvm/BinaryFormat/Dwarf.h"
+#include "llvm/BinaryFormat/ELF.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCSectionELF.h"
+#include "llvm/MC/MCTargetOptions.h"
+#include "llvm/MC/SectionKind.h"
+#include "llvm/Target/TargetMachine.h"
+#include <cassert>
+
+using namespace llvm;
+using namespace dwarf;
+
+//===----------------------------------------------------------------------===//
+// ELF Target
+//===----------------------------------------------------------------------===//
+
+void ARMElfTargetObjectFile::Initialize(MCContext &Ctx,
+ const TargetMachine &TM) {
+ const ARMBaseTargetMachine &ARM_TM = static_cast<const ARMBaseTargetMachine &>(TM);
+ bool isAAPCS_ABI = ARM_TM.TargetABI == ARMBaseTargetMachine::ARMABI::ARM_ABI_AAPCS;
+ bool genExecuteOnly =
+ ARM_TM.getMCSubtargetInfo()->hasFeature(ARM::FeatureExecuteOnly);
+
+ TargetLoweringObjectFileELF::Initialize(Ctx, TM);
+ InitializeELF(isAAPCS_ABI);
+
+ if (isAAPCS_ABI) {
+ LSDASection = nullptr;
+ }
+
+ // Make code section unreadable when in execute-only mode
+ if (genExecuteOnly) {
+ unsigned Type = ELF::SHT_PROGBITS;
+ unsigned Flags =
+ ELF::SHF_EXECINSTR | ELF::SHF_ALLOC | ELF::SHF_ARM_PURECODE;
+ // Since we cannot modify flags for an existing section, we create a new
+ // section with the right flags, and use 0 as the unique ID for
+ // execute-only text
+ TextSection = Ctx.getELFSection(".text", Type, Flags, 0, "", 0U);
+ }
+}
+
+const MCExpr *ARMElfTargetObjectFile::getTTypeGlobalReference(
+ const GlobalValue *GV, unsigned Encoding, const TargetMachine &TM,
+ MachineModuleInfo *MMI, MCStreamer &Streamer) const {
+ if (TM.getMCAsmInfo()->getExceptionHandlingType() != ExceptionHandling::ARM)
+ return TargetLoweringObjectFileELF::getTTypeGlobalReference(
+ GV, Encoding, TM, MMI, Streamer);
+
+ assert(Encoding == DW_EH_PE_absptr && "Can handle absptr encoding only");
+
+ return MCSymbolRefExpr::create(TM.getSymbol(GV),
+ MCSymbolRefExpr::VK_ARM_TARGET2, getContext());
+}
+
+const MCExpr *ARMElfTargetObjectFile::
+getDebugThreadLocalSymbol(const MCSymbol *Sym) const {
+ return MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_ARM_TLSLDO,
+ getContext());
+}
+
+static bool isExecuteOnlyFunction(const GlobalObject *GO, SectionKind SK,
+ const TargetMachine &TM) {
+ if (const Function *F = dyn_cast<Function>(GO))
+ if (TM.getSubtarget<ARMSubtarget>(*F).genExecuteOnly() && SK.isText())
+ return true;
+ return false;
+}
+
+MCSection *ARMElfTargetObjectFile::getExplicitSectionGlobal(
+ const GlobalObject *GO, SectionKind SK, const TargetMachine &TM) const {
+ // Set execute-only access for the explicit section
+ if (isExecuteOnlyFunction(GO, SK, TM))
+ SK = SectionKind::getExecuteOnly();
+
+ return TargetLoweringObjectFileELF::getExplicitSectionGlobal(GO, SK, TM);
+}
+
+MCSection *ARMElfTargetObjectFile::SelectSectionForGlobal(
+ const GlobalObject *GO, SectionKind SK, const TargetMachine &TM) const {
+ // Place the global in the execute-only text section
+ if (isExecuteOnlyFunction(GO, SK, TM))
+ SK = SectionKind::getExecuteOnly();
+
+ return TargetLoweringObjectFileELF::SelectSectionForGlobal(GO, SK, TM);
+}