[ELF] --discard-{locals,all}: mark local symbols referenced by retained non-SHF_ALLOC sections (#209042)
With --gc-sections, mark() does not scan relocations of retained
non-SHF_ALLOC sections, so local symbols referenced only by such
sections (e.g. .L symbols in .debug_str_offsets referenced by
.debug_info) do not get the USED flag.
-r/--emit-relocs with --discard-{locals,all} would discard the symbols
and rewrite relocations to reference the null symbol, corrupting DWARF
in the output. This is common on RISC-V, where
RISCVELFObjectWriter::needsRelocateWithSymbol returns true, but is also
possible on other targets with --reloc-section-sym=none.
Call markUsedLocalSymbols from the retention loop (introduced by
#209035)
to set the flag.
Fix #160789
[SLP] Fix miscompile from unsafe operand-order normalization
IsCommutative(MainOp) is also true for a Sub/FSub feeding only
fabs/icmp-eq-0, but that doesn't make every lane swappable: a
converted Add/FAdd lane's operand order is fixed to preserve its
value, and swapping it into a native Sub/FSub's layout negates it.
Re-check each lane before swapping instead of trusting MainOp's.
Fixes #208944
Reviewers:
Pull Request: https://github.com/llvm/llvm-project/pull/209041
[llvm][HTTP] Apply WinHTTP timeout setting after WinHttpOpen (#188969)
`setTimeout()` required the session handle, but it was only created
inside `HTTPClient::perform()`. This patch stores the incoming value and
applies it after the session handle is created with `WinHttpOpen()`.
---------
Co-authored-by: Nerixyz <nerixdev at outlook.de>
[ELF] Move markUsedLocalSymbols from Writer to markLive. NFC (#209035)
markUsedLocalSymbols (https://reviews.llvm.org/D77807) sets the USED
flag on local symbols referenced by relocations so that -r/--emit-relocs
with --discard-{locals,all} preserves them in the symbol table.
Move the scan into markLive's !gcSections branch to be closer to
MarkLive::resolveReloc. The scan now iterates sections via relsOrRelas,
handling CREL uniformly, and runs in parallel.
This is a step toward fixing #160789
[SLP] Don't truncate compare constants that change value at the demoted width
SLP preserves the original bit width when narrowing compare operands,
but doesn't always account for the required size convertion in LLVM IR.
This can produce incorrect compare constants after truncation.
Fix this by using getSignificantBits() for sign-extended operands,
forbidding truncation for signed predicates on zero-extended operands,
and checking the correct operand in the LBW > RBW case.
