This patch introduces initial-exec model support for thread-local storage
on 64-bit PowerPC ELF.
The patch includes code to handle external assembly and MC output with the
integrated assembler. It intentionally does not support the "old" JIT.
For the initial-exec TLS model, the ABI requires the following to calculate
the address of external thread-local variable x:
Code sequence Relocation Symbol
ld 9,x@got@tprel(2) R_PPC64_GOT_TPREL16_DS x
add 9,9,x@tls R_PPC64_TLS x
The register 9 is arbitrary here. The linker will replace x@got@tprel
with the offset relative to the thread pointer to the generated GOT
entry for symbol x. It will replace x@tls with the thread-pointer
register (13).
The two test cases verify correct assembly output and relocation output
as just described.
PowerPC-specific selection node variants are added for the two
instructions above: LD_GOT_TPREL and ADD_TLS. These are inserted
when an initial-exec global variable is encountered by
PPCTargetLowering::LowerGlobalTLSAddress(), and later lowered to
machine instructions LDgotTPREL and ADD8TLS. LDgotTPREL is a pseudo
that uses the same LDrs support added for medium code model's LDtocL,
with a different relocation type.
The rest of the processing is straightforward.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169281 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCISelLowering.cpp b/lib/Target/PowerPC/PPCISelLowering.cpp
index 0d026c8..1168171 100644
--- a/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -578,6 +578,8 @@
case PPCISD::ADDIS_TOC_HA: return "PPCISD::ADDIS_TOC_HA";
case PPCISD::LD_TOC_L: return "PPCISD::LD_TOC_L";
case PPCISD::ADDI_TOC_L: return "PPCISD::ADDI_TOC_L";
+ case PPCISD::LD_GOT_TPREL: return "PPCISD::LD_GOT_TPREL";
+ case PPCISD::ADD_TLS: return "PPCISD::ADD_TLS";
}
}
@@ -1324,19 +1326,34 @@
EVT PtrVT = getPointerTy();
bool is64bit = PPCSubTarget.isPPC64();
- TLSModel::Model model = getTargetMachine().getTLSModel(GV);
+ TLSModel::Model Model = getTargetMachine().getTLSModel(GV);
- SDValue TGAHi = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
- PPCII::MO_TPREL16_HA);
- SDValue TGALo = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
- PPCII::MO_TPREL16_LO);
+ if (Model == TLSModel::LocalExec) {
+ SDValue TGAHi = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
+ PPCII::MO_TPREL16_HA);
+ SDValue TGALo = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
+ PPCII::MO_TPREL16_LO);
+ SDValue TLSReg = DAG.getRegister(is64bit ? PPC::X13 : PPC::R2,
+ is64bit ? MVT::i64 : MVT::i32);
+ SDValue Hi = DAG.getNode(PPCISD::Hi, dl, PtrVT, TGAHi, TLSReg);
+ return DAG.getNode(PPCISD::Lo, dl, PtrVT, TGALo, Hi);
+ }
- if (model != TLSModel::LocalExec)
- llvm_unreachable("only local-exec TLS mode supported");
- SDValue TLSReg = DAG.getRegister(is64bit ? PPC::X13 : PPC::R2,
+ if (!is64bit)
+ llvm_unreachable("only local-exec is currently supported for ppc32");
+
+ if (Model != TLSModel::InitialExec)
+ llvm_unreachable("only local-exec and initial-exec TLS modes supported");
+
+ SDValue GOTOffset = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
+ PPCII::MO_GOT_TPREL16_DS);
+ SDValue TPReg = DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
+ PPCII::MO_TLS);
+ SDValue GOTReg = DAG.getRegister(is64bit ? PPC::X2 : PPC::R2,
is64bit ? MVT::i64 : MVT::i32);
- SDValue Hi = DAG.getNode(PPCISD::Hi, dl, PtrVT, TGAHi, TLSReg);
- return DAG.getNode(PPCISD::Lo, dl, PtrVT, TGALo, Hi);
+ SDValue TPOffset = DAG.getNode(PPCISD::LD_GOT_TPREL, dl, PtrVT,
+ GOTOffset, GOTReg);
+ return DAG.getNode(PPCISD::ADD_TLS, dl, PtrVT, TPOffset, TPReg);
}
SDValue PPCTargetLowering::LowerGlobalAddress(SDValue Op,