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-rw-r--r--llvm/include/llvm/CodeGen/Analysis.h5
-rw-r--r--llvm/lib/CodeGen/Analysis.cpp43
-rw-r--r--llvm/lib/Target/AArch64/AArch64Subtarget.cpp25
-rw-r--r--llvm/lib/Target/X86/X86Subtarget.cpp44
-rw-r--r--llvm/test/CodeGen/AArch64/pie.ll14
5 files changed, 69 insertions, 62 deletions
diff --git a/llvm/include/llvm/CodeGen/Analysis.h b/llvm/include/llvm/CodeGen/Analysis.h
index 38e64ad3be2..d425fed4212 100644
--- a/llvm/include/llvm/CodeGen/Analysis.h
+++ b/llvm/include/llvm/CodeGen/Analysis.h
@@ -17,10 +17,12 @@
#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/Triple.h"
#include "llvm/CodeGen/ISDOpcodes.h"
#include "llvm/IR/CallSite.h"
#include "llvm/IR/InlineAsm.h"
#include "llvm/IR/Instructions.h"
+#include "llvm/Support/CodeGen.h"
namespace llvm {
class GlobalValue;
@@ -118,6 +120,9 @@ bool returnTypeIsEligibleForTailCall(const Function *F,
// or we are in LTO.
bool canBeOmittedFromSymbolTable(const GlobalValue *GV);
+bool shouldAssumeDSOLocal(Reloc::Model RM, const Triple &TT, const Module &M,
+ const GlobalValue *GV);
+
DenseMap<const MachineBasicBlock *, int>
getFuncletMembership(const MachineFunction &MF);
diff --git a/llvm/lib/CodeGen/Analysis.cpp b/llvm/lib/CodeGen/Analysis.cpp
index 292142b848c..ef405484e84 100644
--- a/llvm/lib/CodeGen/Analysis.cpp
+++ b/llvm/lib/CodeGen/Analysis.cpp
@@ -650,6 +650,49 @@ bool llvm::canBeOmittedFromSymbolTable(const GlobalValue *GV) {
return !GS.IsCompared;
}
+// FIXME: make this a proper option
+static bool CanUseCopyRelocWithPIE = false;
+
+bool llvm::shouldAssumeDSOLocal(Reloc::Model RM, const Triple &TT,
+ const Module &M, const GlobalValue *GV) {
+ // DLLImport explicitly marks the GV as external.
+ if (GV && GV->hasDLLImportStorageClass())
+ return false;
+
+ // Every other GV is local on COFF
+ if (TT.isOSBinFormatCOFF())
+ return true;
+
+ if (RM == Reloc::Static)
+ return true;
+
+ if (GV && (GV->hasLocalLinkage() || !GV->hasDefaultVisibility()))
+ return true;
+
+ if (TT.isOSBinFormatELF()) {
+ assert(RM != Reloc::DynamicNoPIC);
+ // Some linkers can use copy relocations with pie executables.
+ if (M.getPIELevel() != PIELevel::Default) {
+ if (CanUseCopyRelocWithPIE)
+ return true;
+
+ // If the symbol is defined, it cannot be preempted.
+ if (GV && !GV->isDeclarationForLinker())
+ return true;
+ return false;
+ }
+
+ // ELF supports preemption of other symbols.
+ return false;
+ }
+
+ assert(TT.isOSBinFormatMachO());
+ if (GV && GV->isStrongDefinitionForLinker())
+ return true;
+
+ return false;
+}
+
static void collectFuncletMembers(
DenseMap<const MachineBasicBlock *, int> &FuncletMembership, int Funclet,
const MachineBasicBlock *MBB) {
diff --git a/llvm/lib/Target/AArch64/AArch64Subtarget.cpp b/llvm/lib/Target/AArch64/AArch64Subtarget.cpp
index 3cd03e8edd1..7d8aa0c9485 100644
--- a/llvm/lib/Target/AArch64/AArch64Subtarget.cpp
+++ b/llvm/lib/Target/AArch64/AArch64Subtarget.cpp
@@ -14,6 +14,7 @@
#include "AArch64Subtarget.h"
#include "AArch64InstrInfo.h"
#include "AArch64PBQPRegAlloc.h"
+#include "llvm/CodeGen/Analysis.h"
#include "llvm/CodeGen/MachineScheduler.h"
#include "llvm/IR/GlobalValue.h"
#include "llvm/Support/TargetRegistry.h"
@@ -73,39 +74,25 @@ const RegisterBankInfo *AArch64Subtarget::getRegBankInfo() const {
unsigned char
AArch64Subtarget::ClassifyGlobalReference(const GlobalValue *GV,
const TargetMachine &TM) const {
- bool isDef = GV->isStrongDefinitionForLinker();
-
// MachO large model always goes via a GOT, simply to get a single 8-byte
// absolute relocation on all global addresses.
if (TM.getCodeModel() == CodeModel::Large && isTargetMachO())
return AArch64II::MO_GOT;
+ Reloc::Model RM = TM.getRelocationModel();
+ if (!shouldAssumeDSOLocal(RM, TargetTriple, *GV->getParent(), GV))
+ return AArch64II::MO_GOT;
+
// The small code mode's direct accesses use ADRP, which cannot necessarily
// produce the value 0 (if the code is above 4GB).
if (TM.getCodeModel() == CodeModel::Small && GV->hasExternalWeakLinkage()) {
// In PIC mode use the GOT, but in absolute mode use a constant pool load.
- if (TM.getRelocationModel() == Reloc::Static)
+ if (RM == Reloc::Static)
return AArch64II::MO_CONSTPOOL;
else
return AArch64II::MO_GOT;
}
- // If symbol visibility is hidden, the extra load is not needed if
- // the symbol is definitely defined in the current translation unit.
-
- // The handling of non-hidden symbols in PIC mode is rather target-dependent:
- // + On MachO, if the symbol is defined in this module the GOT can be
- // skipped.
- // + On ELF, the R_AARCH64_COPY relocation means that even symbols actually
- // defined could end up in unexpected places. Use a GOT.
- if (TM.getRelocationModel() != Reloc::Static && GV->hasDefaultVisibility()) {
- if (isTargetMachO())
- return isDef ? AArch64II::MO_NO_FLAG : AArch64II::MO_GOT;
- else
- // No need to go through the GOT for local symbols on ELF.
- return GV->hasLocalLinkage() ? AArch64II::MO_NO_FLAG : AArch64II::MO_GOT;
- }
-
return AArch64II::MO_NO_FLAG;
}
diff --git a/llvm/lib/Target/X86/X86Subtarget.cpp b/llvm/lib/Target/X86/X86Subtarget.cpp
index a24b425a4e8..99adf9c459a 100644
--- a/llvm/lib/Target/X86/X86Subtarget.cpp
+++ b/llvm/lib/Target/X86/X86Subtarget.cpp
@@ -14,6 +14,7 @@
#include "X86Subtarget.h"
#include "X86InstrInfo.h"
#include "X86TargetMachine.h"
+#include "llvm/CodeGen/Analysis.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GlobalValue.h"
@@ -50,49 +51,6 @@ unsigned char X86Subtarget::classifyBlockAddressReference() const {
return classifyLocalReference(nullptr);
}
-// FIXME: make this a proper option
-static bool CanUseCopyRelocWithPIE = false;
-
-static bool shouldAssumeDSOLocal(Reloc::Model RM, const Triple &TT,
- const Module &M, const GlobalValue *GV) {
- // DLLImport explicitly marks the GV as external.
- if (GV && GV->hasDLLImportStorageClass())
- return false;
-
- // Every other GV is local on COFF
- if (TT.isOSBinFormatCOFF())
- return true;
-
- if (RM == Reloc::Static)
- return true;
-
- if (GV && (GV->hasLocalLinkage() || !GV->hasDefaultVisibility()))
- return true;
-
- if (TT.isOSBinFormatELF()) {
- assert(RM != Reloc::DynamicNoPIC);
- // Some linkers can use copy relocations with pie executables.
- if (M.getPIELevel() != PIELevel::Default) {
- if (CanUseCopyRelocWithPIE)
- return true;
-
- // If the symbol is defined, it cannot be preempted.
- if (GV && !GV->isDeclarationForLinker())
- return true;
- return false;
- }
-
- // ELF supports preemption of other symbols.
- return false;
- }
-
- assert(TT.isOSBinFormatMachO());
- if (GV && GV->isStrongDefinitionForLinker())
- return true;
-
- return false;
-}
-
/// Classify a global variable reference for the current subtarget according to
/// how we should reference it in a non-pcrel context.
unsigned char
diff --git a/llvm/test/CodeGen/AArch64/pie.ll b/llvm/test/CodeGen/AArch64/pie.ll
new file mode 100644
index 00000000000..5cd27a8761c
--- /dev/null
+++ b/llvm/test/CodeGen/AArch64/pie.ll
@@ -0,0 +1,14 @@
+; RUN: llc -mtriple aarch64-pc-linux -relocation-model=pic < %s | FileCheck %s
+
+@g1 = global i32 42
+
+define i32* @get_g1() {
+; CHECK: get_g1:
+; CHECK: adrp x0, g1
+; CHECK-NEXT: add x0, x0, :lo12:g1
+ ret i32* @g1
+}
+
+!llvm.module.flags = !{!0}
+
+!0 = !{i32 1, !"PIE Level", i32 2}
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