[llvm-branch-commits] [llvm] release/23.x: [Mips] Strip \x01 no-mangle prefix from R_MIPS_JALR symbol name (#219427) (PR #222838)

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llvmorg-github-actions[bot] wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-mips

Author: llvmbot

<details>
<summary>Changes</summary>

Backport f796b25647e378a02482ef383f2db45804d8fb72

Requested by: @<!-- -->brad0

---
Full diff: https://github.com/llvm/llvm-project/pull/222838.diff


3 Files Affected:

- (modified) llvm/lib/Target/Mips/MipsAsmPrinter.cpp (+7-7) 
- (modified) llvm/lib/Target/Mips/MipsAsmPrinter.h (+3) 
- (added) llvm/test/CodeGen/Mips/jalr-no-mangle.ll (+30) 


``````````diff
diff --git a/llvm/lib/Target/Mips/MipsAsmPrinter.cpp b/llvm/lib/Target/Mips/MipsAsmPrinter.cpp
index 62fd0ef319e1a..adda6154e15a5 100644
--- a/llvm/lib/Target/Mips/MipsAsmPrinter.cpp
+++ b/llvm/lib/Target/Mips/MipsAsmPrinter.cpp
@@ -147,21 +147,21 @@ void MipsAsmPrinter::emitPseudoIndirectBranch(MCStreamer &OutStreamer,
 //
 // This is an optimization hint for the linker which may then replace
 // an indirect call with a direct branch.
-static void emitDirectiveRelocJalr(const MachineInstr &MI,
-                                   MCContext &OutContext,
-                                   TargetMachine &TM,
-                                   MCStreamer &OutStreamer,
-                                   const MipsSubtarget &Subtarget) {
+void MipsAsmPrinter::emitDirectiveRelocJalr(const MachineInstr &MI,
+                                            MCContext &OutContext,
+                                            TargetMachine &TM,
+                                            MCStreamer &OutStreamer,
+                                            const MipsSubtarget &Subtarget) {
   for (const MachineOperand &MO :
        llvm::drop_begin(MI.operands(), MI.getDesc().getNumOperands())) {
     if (MO.isMCSymbol() && (MO.getTargetFlags() & MipsII::MO_JALR)) {
       MCSymbol *Callee = MO.getMCSymbol();
       if (Callee && !Callee->getName().empty()) {
+        MCSymbol *Sym = GetExternalSymbolSymbol(Callee->getName());
         MCSymbol *OffsetLabel = OutContext.createTempSymbol();
         const MCExpr *OffsetExpr =
             MCSymbolRefExpr::create(OffsetLabel, OutContext);
-        const MCExpr *CaleeExpr =
-            MCSymbolRefExpr::create(Callee, OutContext);
+        const MCExpr *CaleeExpr = MCSymbolRefExpr::create(Sym, OutContext);
         OutStreamer.emitRelocDirective(
             *OffsetExpr,
             Subtarget.inMicroMipsMode() ? "R_MICROMIPS_JALR" : "R_MIPS_JALR",
diff --git a/llvm/lib/Target/Mips/MipsAsmPrinter.h b/llvm/lib/Target/Mips/MipsAsmPrinter.h
index 6d45ad551db72..ae77c305f9703 100644
--- a/llvm/lib/Target/Mips/MipsAsmPrinter.h
+++ b/llvm/lib/Target/Mips/MipsAsmPrinter.h
@@ -159,6 +159,9 @@ class LLVM_LIBRARY_VISIBILITY MipsAsmPrinter : public AsmPrinter {
   void emitEndOfAsmFile(Module &M) override;
   void PrintDebugValueComment(const MachineInstr *MI, raw_ostream &OS);
   void emitDebugValue(const MCExpr *Value, unsigned Size) const override;
+  void emitDirectiveRelocJalr(const MachineInstr &MI, MCContext &OutContext,
+                              TargetMachine &TM, MCStreamer &OutStreamer,
+                              const MipsSubtarget &Subtarget);
 };
 
 } // end namespace llvm
diff --git a/llvm/test/CodeGen/Mips/jalr-no-mangle.ll b/llvm/test/CodeGen/Mips/jalr-no-mangle.ll
new file mode 100644
index 0000000000000..573328dfab368
--- /dev/null
+++ b/llvm/test/CodeGen/Mips/jalr-no-mangle.ll
@@ -0,0 +1,30 @@
+; RUN: llc -mtriple=mipsel-unknown-linux-gnu -relocation-model=pic < %s | FileCheck %s --check-prefix=ASM
+; RUN: llc -mtriple=mipsel-unknown-linux-gnu -relocation-model=pic -filetype=obj -o %t %s
+; RUN: llvm-readelf -r %t | FileCheck %s --check-prefix=RELOC
+; RUN: llvm-readelf -s %t | FileCheck %s --check-prefix=SYM
+
+declare i32 @"\01my_target_sym"()
+
+define i32 @caller() nounwind {
+; ASM-LABEL: caller:
+; ASM:       # %bb.0: # %entry
+; ASM-NEXT:    lui $2, %hi(_gp_disp)
+; ASM-NEXT:    addiu $2, $2, %lo(_gp_disp)
+; ASM-NEXT:    addiu $sp, $sp, -24
+; ASM-NEXT:    sw $ra, 20($sp)
+; ASM-NEXT:    addu $gp, $2, $25
+; ASM-NEXT:    lw $25, %call16(my_target_sym)($gp)
+; ASM-NEXT:    .reloc $tmp0, R_MIPS_JALR, my_target_sym
+; ASM-NEXT:  $tmp0:
+; ASM-NEXT:    jalr $25
+; ASM-NEXT:    nop
+
+; RELOC: R_MIPS_JALR{{.*}}my_target_sym
+
+; SYM: UND{{.*}}my_target_sym
+; SYM-NOT: UND{{.*}}my_target_sym
+
+entry:
+  %call = call i32 @"\01my_target_sym"()
+  ret i32 %call
+}

``````````

</details>


https://github.com/llvm/llvm-project/pull/222838