Add tests

lld/ELF/SyntheticSections.cpp

@@ -2178,7 +2178,7 @@ void SymbolTableBaseSection::addSymbol(Symbol *b) {
       config->strip != StripPolicy::None) {
     // Including the symbol name to the dynamic symbol table may increase the
     // contract size in more than 20kb, so whenever we want to strip
-    // information, we can assign the same symbol to all local functions.
+    // information, we can assign the same string to all local symbols.
     const static unsigned HiddenOffset =
         strTabSec.addString("hidden_func", false);
     Offset = HiddenOffset;
@@ -2197,8 +2197,8 @@ void SymbolTableBaseSection::sortAndDedupSymbolsByValue() {
                     });
 
   // The linker can assign the same address to two different functions if
-  // their code is the same. When that happens, we must deduplicate symbols
-  // by st_value.
+  // their code is the same (function aliasing). When that happens, we must
+  // deduplicate symbols by st_value.
   symbols.erase(
       std::unique(symbols.begin(), symbols.end(),
                   [](const SymbolTableEntry &a, const SymbolTableEntry &b) {

lld/ELF/Writer.cpp

@@ -2096,7 +2096,7 @@ template <class ELFT> void Writer<ELFT>::finalizeSections() {
             addVerneed(sym);
       } else if (isSbfV3() && includeInSymtab(*sym) && isa<Defined>(sym) &&
                  sym->type == STT_FUNC) {
-        // We need want local functions in the dynamic symbol table for SBFv3
+        // We want local functions in the dynamic symbol table for SBFv3
         const Defined *Def = dyn_cast<Defined>(sym);
         if (shouldKeepInSymtab(*Def)) {
           partitions[sym->partition - 1].dynSymTab->addSymbol(sym);

lld/test/ELF/sbf-dynsyms-dup.s

@@ -0,0 +1,32 @@
+; RUN: ld.lld -z notext -shared -Bdynamic -entry entrypoint %S/Inputs/sbf-dynsyms-dup.o -o %t1.so
+; RUN: llvm-readelf %t1.so --dyn-syms | FileCheck %s
+
+; Ensure no duplicates in case of function aliasing.
+; sbf-dynsyms-dup.o contains the following rust code
+;
+; #[inline(never)]
+; #[no_mangle]
+; pub fn func_1(c: u64) -> u64 {
+;     c % 67
+; }
+;
+; #[inline(never)]
+; #[no_mangle]
+; pub fn func_2(a: u64) -> u64 {
+;     return a % 67;
+; }
+;
+; #[no_mangle]
+; pub unsafe extern "C" fn entrypoint(a: u64, b: u64) -> u64 {
+;     let r1 = func_1(a);
+;     let r2 = func_2(b);
+;     r1 + r2
+; }
+;
+; Compiled with the command:
+; rustc --target sbf-solana-solana --crate-type lib -C panic=abort -C opt-level=2 -C target_cpu=v3 a1.rs -o a1.o
+
+; CHECK:      0: 0000000000000000     0 NOTYPE  LOCAL  DEFAULT   UND
+; CHECK-NEXT: 1: 00000000000002a0    24 FUNC    GLOBAL DEFAULT     6 func_1
+; CHECK-NEXT: 2: 00000000000002b8    56 FUNC    GLOBAL DEFAULT     6 entrypoint
+; CHECK-NOT:  3:

lld/test/ELF/sbf-dynsyms-local.s

@@ -0,0 +1,44 @@
+; RUN: ld.lld -z notext -shared -Bdynamic -entry entrypoint %S/Inputs/sbf-dynsyms-local.o -o %t1.so
+; RUN: llvm-readelf %t1.so --dyn-syms | FileCheck %s
+; RUN: ld.lld -z notext -shared -Bdynamic -entry entrypoint %S/Inputs/sbf-dynsyms-local.o -strip-all -o %t1.so
+; RUN: llvm-readelf %t1.so --dyn-syms | FileCheck --check-prefix=CHECK-STRIP %s
+
+; Ensure local symbols appear in the dynamic symbol table
+; sbf-dynsyms-local.o contains the following rust code
+;
+; #[inline(never)]
+; fn func_1(c: u64) -> u64 {
+;     c % 67
+; }
+;
+; #[inline(never)]
+; fn func_2(a: u64) -> u64 {
+;     return a % 67;
+; }
+;
+; #[no_mangle]
+; pub unsafe extern "C" fn entrypoint(a: u64, b: u64) -> u64 {
+;     let r1 = func_1(a);
+;     let r2 = func_2(b);
+;     r1 + r2
+; }
+;
+; #[inline(never)]
+; fn func_3(c: u64) -> u64 {
+;     c % 68
+; }
+;
+; Compiled with the command:
+; rustc --target sbf-solana-solana --crate-type lib -C panic=abort -C opt-level=2 -C target_cpu=v3 a1.rs -o a1.o
+
+; CHECK:       0: 0000000000000000     0 NOTYPE  LOCAL  DEFAULT   UND
+; CHECK-NEXT:  1: 00000000000002c8    24 FUNC    LOCAL  DEFAULT     5 _ZN2a16func_117he4a7267c4c063035E
+; CHECK-NEXT:  2: 00000000000002e0   104 FUNC    GLOBAL DEFAULT     5 entrypoint
+; CHECK-NEXT:  3: 0000000000000348    24 FUNC    LOCAL  DEFAULT     5 _ZN2a16func_317ha1589f0ded44505fE
+; CHECK-NOT:   4:
+
+; CHECK-STRIP:       0: 0000000000000000     0 NOTYPE  LOCAL  DEFAULT   UND
+; CHECK-STRIP-NEXT:  1: 0000000000000290    24 FUNC    LOCAL  DEFAULT     5 hidden_func
+; CHECK-STRIP-NEXT:  2: 00000000000002a8   104 FUNC    GLOBAL DEFAULT     5 entrypoint
+; CHECK-STRIP-NEXT:  3: 0000000000000310    24 FUNC    LOCAL  DEFAULT     5 hidden_func
+; CHECK-STRIP-NOT:   4: