[llvm] 76f023b - [RISCV] Make mapping symbols SF_FormatSpecific

[Job Noorman via llvm-commits]

Author: Job Noorman
Date: 2023-07-28T10:21:55+02:00
New Revision: 76f023bddfc282017729ff860265191bc9e7c149

URL: https://github.com/llvm/llvm-project/commit/76f023bddfc282017729ff860265191bc9e7c149
DIFF: https://github.com/llvm/llvm-project/commit/76f023bddfc282017729ff860265191bc9e7c149.diff

LOG: [RISCV] Make mapping symbols SF_FormatSpecific

This ensures that llvm-symbolizer ignores them for symbolization.

Note: unlike aarch64-mapping-symbol.s, the test included here does not
test if the mapping symbols are actually in the symbol table. The reason
is that llvm-mc support for RISC-V mapping symbols (D153260) has not
landed yet, so the mapping symbols simply aren't there. However, D153260
would like to depend on this patch together with D156190 to avoid having
to update a large amount of tests.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D156236

Added: 
    llvm/test/DebugInfo/Symbolize/ELF/riscv-mapping-symbol.s

Modified: 
    llvm/include/llvm/Object/ELFObjectFile.h

Removed: 
    


################################################################################
diff  --git a/llvm/include/llvm/Object/ELFObjectFile.h b/llvm/include/llvm/Object/ELFObjectFile.h
index e57ece5443e846..dc3d6bb58710c7 100644
--- a/llvm/include/llvm/Object/ELFObjectFile.h
+++ b/llvm/include/llvm/Object/ELFObjectFile.h
@@ -772,8 +772,10 @@ Expected<uint32_t> ELFObjectFile<ELFT>::getSymbolFlags(DataRefImpl Sym) const {
     }
   } else if (EF.getHeader().e_machine == ELF::EM_RISCV) {
     if (Expected<StringRef> NameOrErr = getSymbolName(Sym)) {
-      // Mark empty name symbols used for label 
diff erences.
-      if (NameOrErr->empty())
+      StringRef Name = *NameOrErr;
+      // Mark empty name symbols (used for label 
diff erences) and mapping
+      // symbols.
+      if (Name.empty() || Name.startswith("$d") || Name.startswith("$x"))
         Result |= SymbolRef::SF_FormatSpecific;
     } else {
       // TODO: Actually report errors helpfully.

diff  --git a/llvm/test/DebugInfo/Symbolize/ELF/riscv-mapping-symbol.s b/llvm/test/DebugInfo/Symbolize/ELF/riscv-mapping-symbol.s
new file mode 100644
index 00000000000000..d290c1736b56c7
--- /dev/null
+++ b/llvm/test/DebugInfo/Symbolize/ELF/riscv-mapping-symbol.s
@@ -0,0 +1,21 @@
+# REQUIRES: riscv-registered-target
+## Ignore RISC-V mapping symbols (with a prefix of $d or $x).
+
+# RUN: llvm-mc -filetype=obj -triple=riscv64 %s -o %t
+# RUN: llvm-symbolizer --obj=%t 0 4 0xc | FileCheck %s
+
+# CHECK:      foo
+# CHECK-NEXT: ??:0:0
+# CHECK-EMPTY:
+# CHECK:      foo
+# CHECK-NEXT: ??:0:0
+# CHECK-EMPTY:
+# CHECK:      foo
+# CHECK-NEXT: ??:0:0
+
+    .global foo
+foo:
+    .word 32
+    nop
+    nop
+    .word 42