[lld] 849951f - [ELF] Fix terminology: TLS optimizations instead of TLS relaxation. NFC

[Fangrui Song via llvm-commits]

Author: Fangrui Song
Date: 2024-01-25T10:17:36-08:00
New Revision: 849951f8759171cb6c74d3ccbcf154506fc1f0ae

URL: https://github.com/llvm/llvm-project/commit/849951f8759171cb6c74d3ccbcf154506fc1f0ae
DIFF: https://github.com/llvm/llvm-project/commit/849951f8759171cb6c74d3ccbcf154506fc1f0ae.diff

LOG: [ELF] Fix terminology: TLS optimizations instead of TLS relaxation. NFC

Added: 
    

Modified: 
    lld/ELF/Relocations.cpp

Removed: 
    


################################################################################
diff  --git a/lld/ELF/Relocations.cpp b/lld/ELF/Relocations.cpp
index b6a317bc3b6d697..3490a701d7189f5 100644
--- a/lld/ELF/Relocations.cpp
+++ b/lld/ELF/Relocations.cpp
@@ -1286,17 +1286,16 @@ static unsigned handleTlsRelocation(RelType type, Symbol &sym,
   }
 
   // ARM, Hexagon, LoongArch and RISC-V do not support GD/LD to IE/LE
-  // relaxation.
+  // optimizations.
   // For PPC64, if the file has missing R_PPC64_TLSGD/R_PPC64_TLSLD, disable
-  // relaxation as well.
-  bool toExecRelax = !config->shared && config->emachine != EM_ARM &&
-                     config->emachine != EM_HEXAGON &&
-                     config->emachine != EM_LOONGARCH &&
-                     config->emachine != EM_RISCV &&
-                     !c.file->ppc64DisableTLSRelax;
+  // optimization as well.
+  bool execOptimize =
+      !config->shared && config->emachine != EM_ARM &&
+      config->emachine != EM_HEXAGON && config->emachine != EM_LOONGARCH &&
+      config->emachine != EM_RISCV && !c.file->ppc64DisableTLSRelax;
 
   // 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.
+  // must be defined and the code sequence can be optimized to use Local-Exec.
   //
   // ARM and RISC-V do not support any relaxations for TLS relocations, however,
   // we can omit the DTPMOD dynamic relocations and resolve them at link time
@@ -1309,8 +1308,8 @@ static unsigned handleTlsRelocation(RelType type, Symbol &sym,
   // module index, with a special value of 0 for the current module. GOT[e1] is
   // unused. There only needs to be one module index entry.
   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 (toExecRelax) {
+    // Local-Dynamic relocs can be optimized to Local-Exec.
+    if (execOptimize) {
       c.addReloc({target->adjustTlsExpr(type, R_RELAX_TLS_LD_TO_LE), type,
                   offset, addend, &sym});
       return target->getTlsGdRelaxSkip(type);
@@ -1322,16 +1321,17 @@ static unsigned handleTlsRelocation(RelType type, Symbol &sym,
     return 1;
   }
 
-  // Local-Dynamic relocs can be relaxed to Local-Exec.
+  // Local-Dynamic relocs can be optimized to Local-Exec.
   if (expr == R_DTPREL) {
-    if (toExecRelax)
+    if (execOptimize)
       expr = target->adjustTlsExpr(type, R_RELAX_TLS_LD_TO_LE);
     c.addReloc({expr, type, offset, addend, &sym});
     return 1;
   }
 
   // Local-Dynamic sequence where offset of tls variable relative to dynamic
-  // thread pointer is stored in the got. This cannot be relaxed to Local-Exec.
+  // thread pointer is stored in the got. This cannot be optimized to
+  // Local-Exec.
   if (expr == R_TLSLD_GOT_OFF) {
     sym.setFlags(NEEDS_GOT_DTPREL);
     c.addReloc({expr, type, offset, addend, &sym});
@@ -1341,13 +1341,13 @@ static unsigned handleTlsRelocation(RelType type, Symbol &sym,
   if (oneof<R_AARCH64_TLSDESC_PAGE, R_TLSDESC, R_TLSDESC_CALL, R_TLSDESC_PC,
             R_TLSDESC_GOTPLT, R_TLSGD_GOT, R_TLSGD_GOTPLT, R_TLSGD_PC,
             R_LOONGARCH_TLSGD_PAGE_PC>(expr)) {
-    if (!toExecRelax) {
+    if (!execOptimize) {
       sym.setFlags(NEEDS_TLSGD);
       c.addReloc({expr, type, offset, addend, &sym});
       return 1;
     }
 
-    // Global-Dynamic relocs can be relaxed to Initial-Exec or Local-Exec
+    // Global-Dynamic/TLSDESC can be optimized to Initial-Exec or Local-Exec
     // depending on the symbol being locally defined or not.
     if (sym.isPreemptible) {
       sym.setFlags(NEEDS_TLSGD_TO_IE);
@@ -1363,9 +1363,9 @@ static unsigned handleTlsRelocation(RelType type, Symbol &sym,
   if (oneof<R_GOT, R_GOTPLT, R_GOT_PC, R_AARCH64_GOT_PAGE_PC,
             R_LOONGARCH_GOT_PAGE_PC, R_GOT_OFF, R_TLSIE_HINT>(expr)) {
     ctx.hasTlsIe.store(true, std::memory_order_relaxed);
-    // Initial-Exec relocs can be relaxed to Local-Exec if the symbol is locally
-    // defined.
-    if (toExecRelax && isLocalInExecutable) {
+    // Initial-Exec relocs can be optimized to Local-Exec if the symbol is
+    // locally defined.
+    if (execOptimize && isLocalInExecutable) {
       c.addReloc({R_RELAX_TLS_IE_TO_LE, type, offset, addend, &sym});
     } else if (expr != R_TLSIE_HINT) {
       sym.setFlags(NEEDS_TLSIE);
@@ -1463,7 +1463,7 @@ template <class ELFT, class RelTy> void RelocationScanner::scanOne(RelTy *&i) {
     in.got->hasGotOffRel.store(true, std::memory_order_relaxed);
   }
 
-  // Process TLS relocations, including relaxing TLS relocations. Note that
+  // Process TLS relocations, including TLS optimizations. Note that
   // R_TPREL and R_TPREL_NEG relocations are resolved in processAux.
   if (sym.isTls()) {
     if (unsigned processed =