Index: llvm/trunk/include/llvm/MC/MCTargetOptions.h =================================================================== --- llvm/trunk/include/llvm/MC/MCTargetOptions.h +++ llvm/trunk/include/llvm/MC/MCTargetOptions.h @@ -41,6 +41,7 @@ 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 @@ ARE_EQUAL(MCSaveTempLabels) && ARE_EQUAL(MCUseDwarfDirectory) && ARE_EQUAL(MCIncrementalLinkerCompatible) && + ARE_EQUAL(MCPIECopyRelocations) && ARE_EQUAL(ShowMCEncoding) && ARE_EQUAL(ShowMCInst) && ARE_EQUAL(AsmVerbose) && Index: llvm/trunk/include/llvm/MC/MCTargetOptionsCommandFlags.h =================================================================== --- llvm/trunk/include/llvm/MC/MCTargetOptionsCommandFlags.h +++ llvm/trunk/include/llvm/MC/MCTargetOptionsCommandFlags.h @@ -38,6 +38,8 @@ "When used with filetype=obj, " "emit an object file which can be used with an incremental linker")); +cl::opt PIECopyRelocations("pie-copy-relocations", cl::desc("PIE Copy Relocations")); + cl::opt DwarfVersion("dwarf-version", cl::desc("Dwarf version"), cl::init(0)); @@ -62,6 +64,7 @@ (AsmInstrumentation == MCTargetOptions::AsmInstrumentationAddress); Options.MCRelaxAll = RelaxAll; Options.MCIncrementalLinkerCompatible = IncrementalLinkerCompatible; + Options.MCPIECopyRelocations = PIECopyRelocations; Options.DwarfVersion = DwarfVersion; Options.ShowMCInst = ShowMCInst; Options.ABIName = ABIName; Index: llvm/trunk/lib/MC/MCTargetOptions.cpp =================================================================== --- llvm/trunk/lib/MC/MCTargetOptions.cpp +++ llvm/trunk/lib/MC/MCTargetOptions.cpp @@ -16,7 +16,8 @@ : 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 { Index: llvm/trunk/lib/Target/TargetMachine.cpp =================================================================== --- llvm/trunk/lib/Target/TargetMachine.cpp +++ llvm/trunk/lib/Target/TargetMachine.cpp @@ -115,9 +115,6 @@ 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 @@ return true; bool IsTLS = GV && GV->isThreadLocal(); + bool IsAccessViaCopyRelocs = + Options.MCOptions.MCPIECopyRelocations && GV && isa(GV); // Check if we can use copy relocations. - if (!IsTLS && (RM == Reloc::Static || CanUseCopyRelocWithPIE)) + if (!IsTLS && (RM == Reloc::Static || IsAccessViaCopyRelocs)) return true; } Index: llvm/trunk/test/CodeGen/X86/global-access-pie-copyrelocs.ll =================================================================== --- llvm/trunk/test/CodeGen/X86/global-access-pie-copyrelocs.ll +++ llvm/trunk/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}