1 files changed, 148 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/Mips/MipsTargetObjectFile.cpp b/contrib/llvm/lib/Target/Mips/MipsTargetObjectFile.cpp
new file mode 100644
index 0000000..b56c39b
--- /dev/null
+++ b/contrib/llvm/lib/Target/Mips/MipsTargetObjectFile.cpp
@@ -0,0 +1,148 @@
+//===-- MipsTargetObjectFile.cpp - Mips Object Files ----------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "MipsTargetObjectFile.h"
+#include "MipsSubtarget.h"
+#include "llvm/IR/DataLayout.h"
+#include "llvm/IR/DerivedTypes.h"
+#include "llvm/IR/GlobalVariable.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCSectionELF.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/ELF.h"
+#include "llvm/Target/TargetMachine.h"
+using namespace llvm;
+
+static cl::opt<unsigned>
+SSThreshold("mips-ssection-threshold", cl::Hidden,
+            cl::desc("Small data and bss section threshold size (default=8)"),
+            cl::init(8));
+
+static cl::opt<bool>
+LocalSData("mlocal-sdata", cl::Hidden,
+           cl::desc("MIPS: Use gp_rel for object-local data."),
+           cl::init(true));
+
+static cl::opt<bool>
+ExternSData("mextern-sdata", cl::Hidden,
+            cl::desc("MIPS: Use gp_rel for data that is not defined by the "
+                     "current object."),
+            cl::init(true));
+
+void MipsTargetObjectFile::Initialize(MCContext &Ctx, const TargetMachine &TM){
+  TargetLoweringObjectFileELF::Initialize(Ctx, TM);
+  InitializeELF(TM.Options.UseInitArray);
+
+  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());
+  this->TM = &TM;
+}
+
+// A address must be loaded from a small section if its size is less than the
+// small section size threshold. Data in this section must be addressed using
+// gp_rel operator.
+static bool IsInSmallSection(uint64_t Size) {
+  // gcc has traditionally not treated zero-sized objects as small data, so this
+  // is effectively part of the ABI.
+  return Size > 0 && Size <= SSThreshold;
+}
+
+/// Return true if this global address should be placed into small data/bss
+/// section.
+bool MipsTargetObjectFile::
+IsGlobalInSmallSection(const GlobalValue *GV, const TargetMachine &TM) const {
+  // We first check the case where global is a declaration, because finding
+  // section kind using getKindForGlobal() is only allowed for global
+  // definitions.
+  if (GV->isDeclaration() || GV->hasAvailableExternallyLinkage())
+    return IsGlobalInSmallSectionImpl(GV, TM);
+
+  return IsGlobalInSmallSection(GV, TM, getKindForGlobal(GV, TM));
+}
+
+/// Return true if this global address should be placed into small data/bss
+/// section.
+bool MipsTargetObjectFile::
+IsGlobalInSmallSection(const GlobalValue *GV, const TargetMachine &TM,
+                       SectionKind Kind) const {
+  return (IsGlobalInSmallSectionImpl(GV, TM) &&
+          (Kind.isDataRel() || Kind.isBSS() || Kind.isCommon()));
+}
+
+/// Return true if this global address should be placed into small data/bss
+/// section. This method does all the work, except for checking the section
+/// kind.
+bool MipsTargetObjectFile::
+IsGlobalInSmallSectionImpl(const GlobalValue *GV,
+                           const TargetMachine &TM) const {
+  const MipsSubtarget &Subtarget = TM.getSubtarget<MipsSubtarget>();
+
+  // Return if small section is not available.
+  if (!Subtarget.useSmallSection())
+    return false;
+
+  // Only global variables, not functions.
+  const GlobalVariable *GVA = dyn_cast<GlobalVariable>(GV);
+  if (!GVA)
+    return false;
+
+  // Enforce -mlocal-sdata.
+  if (!LocalSData && GV->hasLocalLinkage())
+    return false;
+
+  // Enforce -mextern-sdata.
+  if (!ExternSData && ((GV->hasExternalLinkage() && GV->isDeclaration()) ||
+                       GV->hasCommonLinkage()))
+    return false;
+
+  Type *Ty = GV->getType()->getElementType();
+  return IsInSmallSection(
+      TM.getSubtargetImpl()->getDataLayout()->getTypeAllocSize(Ty));
+}
+
+const MCSection *MipsTargetObjectFile::
+SelectSectionForGlobal(const GlobalValue *GV, SectionKind Kind,
+                       Mangler &Mang, const TargetMachine &TM) const {
+  // TODO: Could also support "weak" symbols as well with ".gnu.linkonce.s.*"
+  // sections?
+
+  // Handle Small Section classification here.
+  if (Kind.isBSS() && IsGlobalInSmallSection(GV, TM, Kind))
+    return SmallBSSSection;
+  if (Kind.isDataRel() && IsGlobalInSmallSection(GV, TM, Kind))
+    return SmallDataSection;
+
+  // Otherwise, we work the same as ELF.
+  return TargetLoweringObjectFileELF::SelectSectionForGlobal(GV, Kind, Mang,TM);
+}
+
+/// Return true if this constant should be placed into small data section.
+bool MipsTargetObjectFile::
+IsConstantInSmallSection(const Constant *CN, const TargetMachine &TM) const {
+  return (TM.getSubtarget<MipsSubtarget>().useSmallSection() &&
+          LocalSData &&
+          IsInSmallSection(TM.getSubtargetImpl()->getDataLayout()
+                           ->getTypeAllocSize(CN->getType())));
+}
+
+const MCSection *MipsTargetObjectFile::
+getSectionForConstant(SectionKind Kind, const Constant *C) const {
+  if (IsConstantInSmallSection(C, *TM))
+    return SmallDataSection;
+
+  // Otherwise, we work the same as ELF.
+  return TargetLoweringObjectFileELF::getSectionForConstant(Kind, C);
+}