diff options
| author | Reid Kleckner <rnk@google.com> | 2018-07-23 21:14:35 +0000 |
|---|---|---|
| committer | Reid Kleckner <rnk@google.com> | 2018-07-23 21:14:35 +0000 |
| commit | d59094c7d88e1b703d139b6dec70fde196f27f5c (patch) | |
| tree | 81f96e9c91f95726b66d1cf214546e8df6782f0f /llvm/lib/Target/X86/X86TargetMachine.cpp | |
| parent | fb57ecc1bba9bf8ec6e614b97ca4757089b19a35 (diff) | |
Re-land r335297 "[X86] Implement more of x86-64 large and medium PIC code models"
Don't try to generate large PIC code for non-ELF targets. Neither COFF
nor MachO have relocations for large position independent code, and
users have been using "large PIC" code models to JIT 64-bit code for a
while now. With this change, if they are generating ELF code, their
JITed code will truly be PIC, but if they target MachO or COFF, it will
contain 64-bit immediates that directly reference external symbols. For
a JIT, that's perfectly fine.
Diffstat (limited to 'llvm/lib/Target/X86/X86TargetMachine.cpp')
| -rw-r--r-- | llvm/lib/Target/X86/X86TargetMachine.cpp | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/llvm/lib/Target/X86/X86TargetMachine.cpp b/llvm/lib/Target/X86/X86TargetMachine.cpp index b76e8c20409..374bf3daaf9 100644 --- a/llvm/lib/Target/X86/X86TargetMachine.cpp +++ b/llvm/lib/Target/X86/X86TargetMachine.cpp @@ -160,9 +160,15 @@ static std::string computeDataLayout(const Triple &TT) { } static Reloc::Model getEffectiveRelocModel(const Triple &TT, + bool JIT, Optional<Reloc::Model> RM) { bool is64Bit = TT.getArch() == Triple::x86_64; if (!RM.hasValue()) { + // JIT codegen should use static relocations by default, since it's + // typically executed in process and not relocatable. + if (JIT) + return Reloc::Static; + // Darwin defaults to PIC in 64 bit mode and dynamic-no-pic in 32 bit mode. // Win64 requires rip-rel addressing, thus we force it to PIC. Otherwise we // use static relocation model by default. @@ -214,7 +220,7 @@ X86TargetMachine::X86TargetMachine(const Target &T, const Triple &TT, CodeGenOpt::Level OL, bool JIT) : LLVMTargetMachine( T, computeDataLayout(TT), TT, CPU, FS, Options, - getEffectiveRelocModel(TT, RM), + getEffectiveRelocModel(TT, JIT, RM), getEffectiveCodeModel(CM, JIT, TT.getArch() == Triple::x86_64), OL), TLOF(createTLOF(getTargetTriple())) { // Windows stack unwinder gets confused when execution flow "falls through" |