[lld] d38d0a0 - Revert "[ELF] Simplify getSectionRank"

[Mehdi Amini via llvm-commits]

Author: Mehdi Amini
Date: 2024-05-29T20:32:34-07:00
New Revision: d38d0a0d1bd219555f130dd63e2599f5126e1bdd

URL: https://github.com/llvm/llvm-project/commit/d38d0a0d1bd219555f130dd63e2599f5126e1bdd
DIFF: https://github.com/llvm/llvm-project/commit/d38d0a0d1bd219555f130dd63e2599f5126e1bdd.diff

LOG: Revert "[ELF] Simplify getSectionRank"

This reverts commit f639b57f7993cadb82ee9c36f04703ae4430ed85.

The premerge bot is still broken with failing bolt test.

Added: 
    

Modified: 
    lld/ELF/Writer.cpp

Removed: 
    


################################################################################
diff  --git a/lld/ELF/Writer.cpp b/lld/ELF/Writer.cpp
index c498153f3348b..d2cc6d8ff5f2c 100644
--- a/lld/ELF/Writer.cpp
+++ b/lld/ELF/Writer.cpp
@@ -618,6 +618,7 @@ enum RankFlags {
   RF_NOT_ADDR_SET = 1 << 27,
   RF_NOT_ALLOC = 1 << 26,
   RF_PARTITION = 1 << 18, // Partition number (8 bits)
+  RF_NOT_SPECIAL = 1 << 17,
   RF_LARGE_ALT = 1 << 15,
   RF_WRITE = 1 << 14,
   RF_EXEC_WRITE = 1 << 13,
@@ -643,6 +644,24 @@ unsigned elf::getSectionRank(OutputSection &osec) {
   if (!(osec.flags & SHF_ALLOC))
     return rank | RF_NOT_ALLOC;
 
+  if (osec.type == SHT_LLVM_PART_EHDR)
+    return rank;
+  if (osec.type == SHT_LLVM_PART_PHDR)
+    return rank | 1;
+
+  // Put .interp first because some loaders want to see that section
+  // on the first page of the executable file when loaded into memory.
+  if (osec.name == ".interp")
+    return rank | 2;
+
+  // Put .note sections at the beginning so that they are likely to be included
+  // in a truncate core file. In particular, .note.gnu.build-id, if available,
+  // can identify the object file.
+  if (osec.type == SHT_NOTE)
+    return rank | 3;
+
+  rank |= RF_NOT_SPECIAL;
+
   // Sort sections based on their access permission in the following
   // order: R, RX, RXW, RW(RELRO), RW(non-RELRO).
   //
@@ -658,6 +677,11 @@ unsigned elf::getSectionRank(OutputSection &osec) {
   bool isWrite = osec.flags & SHF_WRITE;
 
   if (!isWrite && !isExec) {
+    // Make PROGBITS sections (e.g .rodata .eh_frame) closer to .text to
+    // alleviate relocation overflow pressure. Large special sections such as
+    // .dynstr and .dynsym can be away from .text.
+    if (osec.type == SHT_PROGBITS)
+      rank |= RF_RODATA;
     // Among PROGBITS sections, place .lrodata further from .text.
     // For -z lrodata-after-bss, place .lrodata after .lbss like GNU ld. This
     // layout has one extra PT_LOAD, but alleviates relocation overflow
@@ -667,25 +691,6 @@ unsigned elf::getSectionRank(OutputSection &osec) {
       rank |= config->zLrodataAfterBss ? RF_LARGE_ALT : 0;
     else
       rank |= config->zLrodataAfterBss ? 0 : RF_LARGE;
-
-    if (osec.type == SHT_LLVM_PART_EHDR)
-      ;
-    else if (osec.type == SHT_LLVM_PART_PHDR)
-      rank |= 1;
-    else if (osec.name == ".interp")
-      rank |= 2;
-    // Put .note sections at the beginning so that they are likely to be
-    // included in a truncate core file. In particular, .note.gnu.build-id, if
-    // available, can identify the object file.
-    else if (osec.type == SHT_NOTE)
-      rank |= 3;
-    // Make PROGBITS sections (e.g .rodata .eh_frame) closer to .text to
-    // alleviate relocation overflow pressure. Large special sections such as
-    // .dynstr and .dynsym can be away from .text.
-    else if (osec.type != SHT_PROGBITS)
-      rank |= 4;
-    else
-      rank |= RF_RODATA;
   } else if (isExec) {
     rank |= isWrite ? RF_EXEC_WRITE : RF_EXEC;
   } else {