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-rw-r--r--llvm/include/llvm/MC/MCTargetOptions.h2
-rw-r--r--llvm/include/llvm/MC/MCTargetOptionsCommandFlags.h3
-rw-r--r--llvm/lib/MC/MCTargetOptions.cpp3
-rw-r--r--llvm/lib/Target/TargetMachine.cpp7
-rw-r--r--llvm/test/CodeGen/X86/global-access-pie-copyrelocs.ll119
5 files changed, 129 insertions, 5 deletions
diff --git a/llvm/include/llvm/MC/MCTargetOptions.h b/llvm/include/llvm/MC/MCTargetOptions.h
index fd4c6e4e4fb..21091b378f8 100644
--- a/llvm/include/llvm/MC/MCTargetOptions.h
+++ b/llvm/include/llvm/MC/MCTargetOptions.h
@@ -41,6 +41,7 @@ public:
bool MCSaveTempLabels : 1;
bool MCUseDwarfDirectory : 1;
bool MCIncrementalLinkerCompatible : 1;
+ bool MCPIECopyRelocations : 1;
bool ShowMCEncoding : 1;
bool ShowMCInst : 1;
bool AsmVerbose : 1;
@@ -67,6 +68,7 @@ inline bool operator==(const MCTargetOptions &LHS, const MCTargetOptions &RHS) {
ARE_EQUAL(MCSaveTempLabels) &&
ARE_EQUAL(MCUseDwarfDirectory) &&
ARE_EQUAL(MCIncrementalLinkerCompatible) &&
+ ARE_EQUAL(MCPIECopyRelocations) &&
ARE_EQUAL(ShowMCEncoding) &&
ARE_EQUAL(ShowMCInst) &&
ARE_EQUAL(AsmVerbose) &&
diff --git a/llvm/include/llvm/MC/MCTargetOptionsCommandFlags.h b/llvm/include/llvm/MC/MCTargetOptionsCommandFlags.h
index 801dd6a2d50..cb020845801 100644
--- a/llvm/include/llvm/MC/MCTargetOptionsCommandFlags.h
+++ b/llvm/include/llvm/MC/MCTargetOptionsCommandFlags.h
@@ -38,6 +38,8 @@ cl::opt<bool> IncrementalLinkerCompatible(
"When used with filetype=obj, "
"emit an object file which can be used with an incremental linker"));
+cl::opt<bool> PIECopyRelocations("pie-copy-relocations", cl::desc("PIE Copy Relocations"));
+
cl::opt<int> DwarfVersion("dwarf-version", cl::desc("Dwarf version"),
cl::init(0));
@@ -62,6 +64,7 @@ static inline MCTargetOptions InitMCTargetOptionsFromFlags() {
(AsmInstrumentation == MCTargetOptions::AsmInstrumentationAddress);
Options.MCRelaxAll = RelaxAll;
Options.MCIncrementalLinkerCompatible = IncrementalLinkerCompatible;
+ Options.MCPIECopyRelocations = PIECopyRelocations;
Options.DwarfVersion = DwarfVersion;
Options.ShowMCInst = ShowMCInst;
Options.ABIName = ABIName;
diff --git a/llvm/lib/MC/MCTargetOptions.cpp b/llvm/lib/MC/MCTargetOptions.cpp
index 1d956a8ffce..e847a17dfec 100644
--- a/llvm/lib/MC/MCTargetOptions.cpp
+++ b/llvm/lib/MC/MCTargetOptions.cpp
@@ -16,7 +16,8 @@ MCTargetOptions::MCTargetOptions()
: SanitizeAddress(false), MCRelaxAll(false), MCNoExecStack(false),
MCFatalWarnings(false), MCNoWarn(false), MCSaveTempLabels(false),
MCUseDwarfDirectory(false), MCIncrementalLinkerCompatible(false),
- ShowMCEncoding(false), ShowMCInst(false), AsmVerbose(false),
+ MCPIECopyRelocations(false), ShowMCEncoding(false),
+ ShowMCInst(false), AsmVerbose(false),
PreserveAsmComments(true), DwarfVersion(0), ABIName() {}
StringRef MCTargetOptions::getABIName() const {
diff --git a/llvm/lib/Target/TargetMachine.cpp b/llvm/lib/Target/TargetMachine.cpp
index 43a587ba847..792280af84d 100644
--- a/llvm/lib/Target/TargetMachine.cpp
+++ b/llvm/lib/Target/TargetMachine.cpp
@@ -115,9 +115,6 @@ static TLSModel::Model getSelectedTLSModel(const GlobalValue *GV) {
llvm_unreachable("invalid TLS model");
}
-// FIXME: make this a proper option
-static bool CanUseCopyRelocWithPIE = false;
-
bool TargetMachine::shouldAssumeDSOLocal(const Module &M,
const GlobalValue *GV) const {
Reloc::Model RM = getRelocationModel();
@@ -154,8 +151,10 @@ bool TargetMachine::shouldAssumeDSOLocal(const Module &M,
return true;
bool IsTLS = GV && GV->isThreadLocal();
+ bool IsAccessViaCopyRelocs =
+ Options.MCOptions.MCPIECopyRelocations && GV && isa<GlobalVariable>(GV);
// Check if we can use copy relocations.
- if (!IsTLS && (RM == Reloc::Static || CanUseCopyRelocWithPIE))
+ if (!IsTLS && (RM == Reloc::Static || IsAccessViaCopyRelocs))
return true;
}
diff --git a/llvm/test/CodeGen/X86/global-access-pie-copyrelocs.ll b/llvm/test/CodeGen/X86/global-access-pie-copyrelocs.ll
new file mode 100644
index 00000000000..5c4a87c969c
--- /dev/null
+++ b/llvm/test/CodeGen/X86/global-access-pie-copyrelocs.ll
@@ -0,0 +1,119 @@
+; RUN: llc < %s -march=x86-64 -mcpu=generic -mtriple=x86_64-linux-gnu -relocation-model=pic -pie-copy-relocations \
+; RUN: | FileCheck -check-prefix=X64 %s
+; RUN: llc < %s -emulated-tls -march=x86 -mcpu=generic -mtriple=i386-linux-gnu -relocation-model=pic -pie-copy-relocations \
+; RUN: | FileCheck -check-prefix=X32 %s
+
+; External Linkage
+@a = global i32 0, align 4
+
+define i32 @my_access_global_a() #0 {
+; X32-LABEL: my_access_global_a:
+; X32: addl $_GLOBAL_OFFSET_TABLE_{{.*}}, %eax
+; X32-NEXT: movl a@GOTOFF(%eax), %eax
+; X64-LABEL: my_access_global_a:
+; X64: movl a(%rip), %eax
+
+entry:
+ %0 = load i32, i32* @a, align 4
+ ret i32 %0
+}
+
+; WeakAny Linkage
+@b = weak global i32 0, align 4
+
+define i32 @my_access_global_b() #0 {
+; X32-LABEL: my_access_global_b:
+; X32: addl $_GLOBAL_OFFSET_TABLE_{{.*}}, %eax
+; X32-NEXT: movl b@GOTOFF(%eax), %eax
+; X64-LABEL: my_access_global_b:
+; X64: movl b(%rip), %eax
+
+entry:
+ %0 = load i32, i32* @b, align 4
+ ret i32 %0
+}
+
+; Internal Linkage
+@c = internal global i32 0, align 4
+
+define i32 @my_access_global_c() #0 {
+; X32-LABEL: my_access_global_c:
+; X32: addl $_GLOBAL_OFFSET_TABLE_{{.*}}, %eax
+; X32-NEXT: movl c@GOTOFF(%eax), %eax
+; X64-LABEL: my_access_global_c:
+; X64: movl c(%rip), %eax
+
+entry:
+ %0 = load i32, i32* @c, align 4
+ ret i32 %0
+}
+
+; External Linkage, only declaration.
+@d = external global i32, align 4
+
+define i32 @my_access_global_load_d() #0 {
+; X32-LABEL: my_access_global_load_d:
+; X32: addl $_GLOBAL_OFFSET_TABLE_{{.*}}, %eax
+; X32-NEXT: movl d@GOTOFF(%eax), %eax
+; X64-LABEL: my_access_global_load_d:
+; X64: movl d(%rip), %eax
+
+entry:
+ %0 = load i32, i32* @d, align 4
+ ret i32 %0
+}
+
+; External Linkage, only declaration, store a value.
+
+define i32 @my_access_global_store_d() #0 {
+; X32-LABEL: my_access_global_store_d:
+; X32: addl $_GLOBAL_OFFSET_TABLE_{{.*}}, %eax
+; X32-NEXT: movl $2, d@GOTOFF(%eax)
+; X64-LABEL: my_access_global_store_d:
+; X64: movl $2, d(%rip)
+
+entry:
+ store i32 2, i32* @d, align 4
+ ret i32 0
+}
+
+; External Linkage, function pointer access.
+declare i32 @access_fp(i32 ()*)
+declare i32 @foo()
+
+define i32 @my_access_fp_foo() #0 {
+; X32-LABEL: my_access_fp_foo:
+; X32: addl $_GLOBAL_OFFSET_TABLE_{{.*}}, %ebx
+; X32-NEXT: movl foo@GOT(%ebx), %eax
+; X64-LABEL: my_access_fp_foo:
+; X64: movq foo@GOTPCREL(%rip), %rdi
+
+entry:
+ %call = call i32 @access_fp(i32 ()* @foo)
+ ret i32 %call
+}
+
+; LinkOnceODR Linkage, function pointer access.
+
+$bar = comdat any
+
+define linkonce_odr i32 @bar() comdat {
+entry:
+ ret i32 0
+}
+
+define i32 @my_access_fp_bar() #0 {
+; X32-LABEL: my_access_fp_bar:
+; X32: addl $_GLOBAL_OFFSET_TABLE_{{.*}}, %ebx
+; X32-NEXT: leal bar@GOTOFF(%ebx), %eax
+; X64-LABEL: my_access_fp_bar:
+; X64: leaq bar(%rip), %rdi
+
+entry:
+ %call = call i32 @access_fp(i32 ()* @bar)
+ ret i32 %call
+}
+
+!llvm.module.flags = !{!0, !1}
+!0 = !{i32 1, !"PIC Level", i32 1}
+!1 = !{i32 1, !"PIE Level", i32 1}
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