[llvm] [PAC][CodeGen][ELF][AArch64] Support signed TLSDESC (PR #113813)

[Anatoly Trosinenko via llvm-commits]

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@@ -2730,6 +2730,55 @@ void AArch64AsmPrinter::emitInstruction(const MachineInstr *MI) {
     EmitToStreamer(*OutStreamer, TmpInstSB);
     return;
   }
+  case AArch64::TLSDESC_AUTH_CALLSEQ: {
+    /// lower this to:
+    ///    adrp  x0, :tlsdesc_auth:var
+    ///    ldr   x16, [x0, #:tlsdesc_auth_lo12:var]
+    ///    add   x0, x0, #:tlsdesc_auth_lo12:var
+    ///    blraa x16, x0
+    ///    (TPIDR_EL0 offset now in x0)
+    const MachineOperand &MO_Sym = MI->getOperand(0);
+    MachineOperand MO_TLSDESC_LO12(MO_Sym), MO_TLSDESC(MO_Sym);
+    MCOperand Sym, SymTLSDescLo12, SymTLSDesc;
+    MO_TLSDESC_LO12.setTargetFlags(AArch64II::MO_TLS | AArch64II::MO_PAGEOFF);
+    MO_TLSDESC.setTargetFlags(AArch64II::MO_TLS | AArch64II::MO_PAGE);
+    MCInstLowering.lowerOperand(MO_Sym, Sym);
+    MCInstLowering.lowerOperand(MO_TLSDESC_LO12, SymTLSDescLo12);
+    MCInstLowering.lowerOperand(MO_TLSDESC, SymTLSDesc);
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atrosinenko wrote:

Looks like `MCOperand Sym` is unused here: in `TLSDESC_CALLSEQ` it is passed to `TLSDESCCALL` instruction but here we don't emit one.

https://github.com/llvm/llvm-project/pull/113813