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Revert "[ELF] Simplify getSectionRank"

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This reverts commit f639b57f7993cadb82ee9c36f04703ae4430ed85.

The premerge bot is still broken with failing bolt test.
This commit is contained in:
Mehdi Amini 2024-05-29 20:32:34 -07:00
parent f639b57f79
commit d38d0a0d1b
1 changed files with 24 additions and 19 deletions
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43
lld/ELF/Writer.cpp
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@ -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 {