[PATCH] D83243: [ELF] Rename canRelax to sharedToExecRelax. NFC

[Fangrui Song via Phabricator via llvm-commits]

MaskRay created this revision.
MaskRay added reviewers: grimar, psmith, ruiu.
Herald added subscribers: llvm-commits, s.egerton, simoncook, arichardson, emaste.
Herald added a reviewer: espindola.
Herald added a project: LLVM.

In the absence of TLS relaxation (rewrite of code sequences),
there is still an applicable optimization:

[gd]: General Dynamic: resolve DTPMOD to 1 and/or resolve DTPOFF statically

All the other relaxations are only performed when !config->shared.
Since [gd] is handled differently, we can fold !config->shared into
canRelax and simplify its use sites. Rename it to reflect to new semantics.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D83243

Files:
  lld/ELF/Relocations.cpp


Index: lld/ELF/Relocations.cpp
===================================================================
--- lld/ELF/Relocations.cpp
+++ lld/ELF/Relocations.cpp
@@ -197,9 +197,9 @@
     return 1;
   }
 
-  bool canRelax = config->emachine != EM_ARM &&
-                  config->emachine != EM_HEXAGON &&
-                  config->emachine != EM_RISCV;
+  bool sharedToExecRelax = !config->shared && config->emachine != EM_ARM &&
+                           config->emachine != EM_HEXAGON &&
+                           config->emachine != EM_RISCV;
 
   // If we are producing an executable and the symbol is non-preemptable, it
   // must be defined and the code sequence can be relaxed to use Local-Exec.
@@ -217,7 +217,7 @@
   if (oneof<R_TLSLD_GOT, R_TLSLD_GOTPLT, R_TLSLD_PC, R_TLSLD_HINT>(
           expr)) {
     // Local-Dynamic relocs can be relaxed to Local-Exec.
-    if (canRelax && !config->shared) {
+    if (sharedToExecRelax) {
       c.relocations.push_back(
           {target->adjustRelaxExpr(type, nullptr, R_RELAX_TLS_LD_TO_LE), type,
            offset, addend, &sym});
@@ -238,7 +238,7 @@
   }
 
   // Local-Dynamic relocs can be relaxed to Local-Exec.
-  if (expr == R_DTPREL && canRelax && !config->shared) {
+  if (expr == R_DTPREL && sharedToExecRelax) {
     c.relocations.push_back(
         {target->adjustRelaxExpr(type, nullptr, R_RELAX_TLS_LD_TO_LE), type,
          offset, addend, &sym});
@@ -260,7 +260,7 @@
 
   if (oneof<R_AARCH64_TLSDESC_PAGE, R_TLSDESC, R_TLSDESC_CALL, R_TLSDESC_PC,
             R_TLSGD_GOT, R_TLSGD_GOTPLT, R_TLSGD_PC>(expr)) {
-    if (!canRelax || config->shared) {
+    if (!sharedToExecRelax) {
       if (in.got->addDynTlsEntry(sym)) {
         uint64_t off = in.got->getGlobalDynOffset(sym);
 
@@ -308,7 +308,7 @@
   // defined.
   if (oneof<R_GOT, R_GOTPLT, R_GOT_PC, R_AARCH64_GOT_PAGE_PC, R_GOT_OFF,
             R_TLSIE_HINT>(expr) &&
-      canRelax && isLocalInExecutable) {
+      sharedToExecRelax && isLocalInExecutable) {
     c.relocations.push_back({R_RELAX_TLS_IE_TO_LE, type, offset, addend, &sym});
     return 1;
   }


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