Hexagon backend support
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146412 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/Hexagon/HexagonTargetObjectFile.cpp b/lib/Target/Hexagon/HexagonTargetObjectFile.cpp
new file mode 100644
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--- /dev/null
+++ b/lib/Target/Hexagon/HexagonTargetObjectFile.cpp
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+//===-- HexagonTargetObjectFile.cpp - Hexagon asm properties ----*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file contains the declarations of the HexagonTargetAsmInfo properties.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Function.h"
+#include "llvm/GlobalVariable.h"
+#include "llvm/Target/TargetData.h"
+#include "llvm/DerivedTypes.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/Support/ELF.h"
+#include "llvm/Support/CommandLine.h"
+#include "HexagonSubtarget.h"
+#include "HexagonTargetObjectFile.h"
+#include "HexagonTargetMachine.h"
+
+using namespace llvm;
+
+static cl::opt<int> SmallDataThreshold("hexagon-small-data-threshold",
+ cl::init(8), cl::Hidden);
+
+void HexagonTargetObjectFile::Initialize(MCContext &Ctx,
+ const TargetMachine &TM) {
+ TargetLoweringObjectFileELF::Initialize(Ctx, TM);
+
+
+ SmallDataSection =
+ getContext().getELFSection(".sdata", ELF::SHT_PROGBITS,
+ ELF::SHF_WRITE | ELF::SHF_ALLOC,
+ SectionKind::getDataRel());
+ SmallBSSSection =
+ getContext().getELFSection(".sbss", ELF::SHT_NOBITS,
+ ELF::SHF_WRITE | ELF::SHF_ALLOC,
+ SectionKind::getBSS());
+}
+
+// sdata/sbss support taken largely from the MIPS Backend.
+static bool IsInSmallSection(uint64_t Size) {
+ return Size > 0 && Size <= (uint64_t)SmallDataThreshold;
+}
+/// IsGlobalInSmallSection - Return true if this global value should be
+/// placed into small data/bss section.
+bool HexagonTargetObjectFile::IsGlobalInSmallSection(const GlobalValue *GV,
+ const TargetMachine &TM) const {
+ // If the primary definition of this global value is outside the current
+ // translation unit or the global value is available for inspection but not
+ // emission, then do nothing.
+ if (GV->isDeclaration() || GV->hasAvailableExternallyLinkage())
+ return false;
+
+ // Otherwise, Check if GV should be in sdata/sbss, when normally it would end
+ // up in getKindForGlobal(GV, TM).
+ return IsGlobalInSmallSection(GV, TM, getKindForGlobal(GV, TM));
+}
+
+/// IsGlobalInSmallSection - Return true if this global value should be
+/// placed into small data/bss section.
+bool HexagonTargetObjectFile::
+IsGlobalInSmallSection(const GlobalValue *GV, const TargetMachine &TM,
+ SectionKind Kind) const {
+ // Only global variables, not functions.
+ const GlobalVariable *GVA = dyn_cast<GlobalVariable>(GV);
+ if (!GVA)
+ return false;
+
+ if (Kind.isBSS() || Kind.isDataNoRel() || Kind.isCommon()) {
+ Type *Ty = GV->getType()->getElementType();
+ return IsInSmallSection(TM.getTargetData()->getTypeAllocSize(Ty));
+ }
+
+ return false;
+}
+
+const MCSection *HexagonTargetObjectFile::
+SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
+ Mangler *Mang, const TargetMachine &TM) const {
+
+ // Handle Small Section classification here.
+ if (Kind.isBSS() && IsGlobalInSmallSection(GV, TM, Kind))
+ return SmallBSSSection;
+ if (Kind.isDataNoRel() && IsGlobalInSmallSection(GV, TM, Kind))
+ return SmallDataSection;
+
+ // Otherwise, we work the same as ELF.
+ return TargetLoweringObjectFileELF::SelectSectionForGlobal(GV, Kind, Mang,TM);
+}