This patch improves the 64-bit PowerPC InitialExec TLS support by providing
for a wider range of GOT entries that can hold thread-relative offsets.
This matches the behavior of GCC, which was not documented in the PPC64 TLS
ABI. The ABI will be updated with the new code sequence.
Former sequence:
ld 9,x@got@tprel(2)
add 9,9,x@tls
New sequence:
addis 9,2,x@got@tprel@ha
ld 9,x@got@tprel@l(9)
add 9,9,x@tls
Note that a linker optimization exists to transform the new sequence into
the shorter sequence when appropriate, by replacing the addis with a nop
and modifying the base register and relocation type of the ld.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170209 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/PowerPC/PPCAsmPrinter.cpp b/lib/Target/PowerPC/PPCAsmPrinter.cpp
index 0ebf891..35b6234 100644
--- a/lib/Target/PowerPC/PPCAsmPrinter.cpp
+++ b/lib/Target/PowerPC/PPCAsmPrinter.cpp
@@ -513,8 +513,24 @@
OutStreamer.EmitInstruction(TmpInst);
return;
}
- case PPC::LDgotTPREL: {
- // Transform %Xd = LDgotTPREL <ga:@sym>, %Xs
+ case PPC::ADDISgotTprelHA: {
+ // Transform: %Xd = ADDISgotTprelHA %X2, <ga:@sym>
+ // Into: %Xd = ADDIS8 %X2, sym@got@tlsgd@ha
+ assert(Subtarget.isPPC64() && "Not supported for 32-bit PowerPC");
+ const MachineOperand &MO = MI->getOperand(2);
+ const GlobalValue *GValue = MO.getGlobal();
+ MCSymbol *MOSymbol = Mang->getSymbol(GValue);
+ const MCExpr *SymGotTprel =
+ MCSymbolRefExpr::Create(MOSymbol, MCSymbolRefExpr::VK_PPC_GOT_TPREL16_HA,
+ OutContext);
+ OutStreamer.EmitInstruction(MCInstBuilder(PPC::ADDIS8)
+ .addReg(MI->getOperand(0).getReg())
+ .addReg(PPC::X2)
+ .addExpr(SymGotTprel));
+ return;
+ }
+ case PPC::LDgotTprelL: {
+ // Transform %Xd = LDgotTprelL <ga:@sym>, %Xs
LowerPPCMachineInstrToMCInst(MI, TmpInst, *this, Subtarget.isDarwin());
// Change the opcode to LDrs, which is a form of LD with the offset
@@ -524,7 +540,7 @@
const GlobalValue *GValue = MO.getGlobal();
MCSymbol *MOSymbol = Mang->getSymbol(GValue);
const MCExpr *Exp =
- MCSymbolRefExpr::Create(MOSymbol, MCSymbolRefExpr::VK_PPC_GOT_TPREL16_DS,
+ MCSymbolRefExpr::Create(MOSymbol, MCSymbolRefExpr::VK_PPC_GOT_TPREL16_LO,
OutContext);
TmpInst.getOperand(1) = MCOperand::CreateExpr(Exp);
OutStreamer.EmitInstruction(TmpInst);