[lld] 33319dd - [ELF] LTO: skip expensive usedStartStop initialization if bitcodeFiles.empty()

[Fangrui Song via llvm-commits]

Author: Fangrui Song
Date: 2021-12-23T01:52:54-08:00
New Revision: 33319dde2a4f594ba763f82e89b7cf4024416ff8

URL: https://github.com/llvm/llvm-project/commit/33319dde2a4f594ba763f82e89b7cf4024416ff8
DIFF: https://github.com/llvm/llvm-project/commit/33319dde2a4f594ba763f82e89b7cf4024416ff8.diff

LOG: [ELF] LTO: skip expensive usedStartStop initialization if bitcodeFiles.empty()

This may cost 1.3+% of total link time.

Added: 
    

Modified: 
    lld/ELF/LTO.cpp

Removed: 
    


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diff  --git a/lld/ELF/LTO.cpp b/lld/ELF/LTO.cpp
index b1632b8bae8a..65b943c4a54c 100644
--- a/lld/ELF/LTO.cpp
+++ b/lld/ELF/LTO.cpp
@@ -204,6 +204,8 @@ BitcodeCompiler::BitcodeCompiler() {
                                        config->ltoPartitions);
 
   // Initialize usedStartStop.
+  if (bitcodeFiles.empty())
+    return;
   for (Symbol *sym : symtab->symbols()) {
     StringRef s = sym->getName();
     for (StringRef prefix : {"__start_", "__stop_"})