[llvm] [RISCV] Create mapping symbols with non-unique names (PR #99903)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-risc-v

Author: Fangrui Song (MaskRay)

<details>
<summary>Changes</summary>

Similar to #<!-- -->99836 for AArch64.

Non-unique names save .strtab space and match GNU assembler.


---
Full diff: https://github.com/llvm/llvm-project/pull/99903.diff


3 Files Affected:

- (modified) llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.cpp (+1-3) 
- (modified) llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.h (-1) 
- (modified) llvm/test/MC/RISCV/mapping-across-sections.s (+5-5) 


``````````diff
diff --git a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.cpp b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.cpp
index 87c5a756e0258..0100e0614d619 100644
--- a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.cpp
+++ b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.cpp
@@ -132,7 +132,6 @@ void RISCVTargetELFStreamer::emitDirectiveVariantCC(MCSymbol &Symbol) {
 void RISCVELFStreamer::reset() {
   static_cast<RISCVTargetStreamer *>(getTargetStreamer())->reset();
   MCELFStreamer::reset();
-  MappingSymbolCounter = 0;
   LastMappingSymbols.clear();
   LastEMS = EMS_None;
 }
@@ -152,8 +151,7 @@ void RISCVELFStreamer::emitInstructionsMappingSymbol() {
 }
 
 void RISCVELFStreamer::emitMappingSymbol(StringRef Name) {
-  auto *Symbol = cast<MCSymbolELF>(getContext().getOrCreateSymbol(
-      Name + "." + Twine(MappingSymbolCounter++)));
+  auto *Symbol = cast<MCSymbolELF>(getContext().createLocalSymbol(Name));
   emitLabel(Symbol);
   Symbol->setType(ELF::STT_NOTYPE);
   Symbol->setBinding(ELF::STB_LOCAL);
diff --git a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.h b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.h
index 40c6b5ac3dcc8..b06760859483d 100644
--- a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.h
+++ b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFStreamer.h
@@ -22,7 +22,6 @@ class RISCVELFStreamer : public MCELFStreamer {
 
   enum ElfMappingSymbol { EMS_None, EMS_Instructions, EMS_Data };
 
-  int64_t MappingSymbolCounter = 0;
   DenseMap<const MCSection *, ElfMappingSymbol> LastMappingSymbols;
   ElfMappingSymbol LastEMS = EMS_None;
 
diff --git a/llvm/test/MC/RISCV/mapping-across-sections.s b/llvm/test/MC/RISCV/mapping-across-sections.s
index 700e86a0eb70e..11b05a616bdcf 100644
--- a/llvm/test/MC/RISCV/mapping-across-sections.s
+++ b/llvm/test/MC/RISCV/mapping-across-sections.s
@@ -1,5 +1,5 @@
-# RUN: llvm-mc -triple=riscv32 -filetype=obj < %s | llvm-readelf -Ss - | FileCheck %s
-# RUN: llvm-mc -triple=riscv64 -filetype=obj < %s | llvm-readelf -Ss - | FileCheck %s
+# RUN: llvm-mc -triple=riscv32 -filetype=obj %s | llvm-readelf -Ss - | FileCheck %s
+# RUN: llvm-mc -triple=riscv64 -filetype=obj %s | llvm-readelf -Ss - | FileCheck %s
 
         .text
         nop
@@ -28,6 +28,6 @@
 # CHECK: [[#STARTS_DATA:]]] .starts_data
 
 # CHECK:    Value  Size Type    Bind   Vis     Ndx              Name
-# CHECK: 00000000     0 NOTYPE  LOCAL  DEFAULT [[#TEXT]]        $x
-# CHECK: 00000000     0 NOTYPE  LOCAL  DEFAULT [[#WIBBLE]]      $x
-# CHECK: 00000000     0 NOTYPE  LOCAL  DEFAULT [[#STARTS_DATA]] $d
+# CHECK: 00000000     0 NOTYPE  LOCAL  DEFAULT [[#TEXT]]        $x{{$}}
+# CHECK: 00000000     0 NOTYPE  LOCAL  DEFAULT [[#WIBBLE]]      $x{{$}}
+# CHECK: 00000000     0 NOTYPE  LOCAL  DEFAULT [[#STARTS_DATA]] $d{{$}}

``````````

</details>


https://github.com/llvm/llvm-project/pull/99903