feat(ppc64): REL24 local entry plus REL32/ADDR32/REL64#1999
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| RelocationKind::Absolute, | ||
| RelocationSize::ByteSize(4), | ||
| // Can represent either a signed or an unsigned 32-bit value. | ||
| AllowedRange::new(-(2i64.pow(31)), 2i64.pow(32)), |
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Does a negative absolute address make sense? What does it mean?
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I merely match the binutils' complain_overflow_bitfield. The R_AARCH64_ABS32 in linker-utils/src/aarch64.rs is also the same. Hence my decision to keep it that way for consistency. Having said that I am more than happy to make it stricter as you suggested.
ELFv2 functions that set up r2 have a separate local entry point. For a direct call that already shares the callee's TOC, branch to that local entry (skipping the global-entry prologue) by adding the callee's st_other local-entry offset to the branch target. Functions with no separate local entry (offset 0) are unaffected.
REL32 (32-bit PC-relative, used pervasively by .eh_frame) and ADDR32 (32-bit absolute). Both are simple 4-byte values.
R_PPC64_REL64 (64-bit PC-relative), an 8-byte value mirroring REL32.
davidlattimore
approved these changes
May 31, 2026
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Extends the ppc64le static-relocation support added in #1977 with the
remaining pieces needed for a static link to come out correct on ELFv2:
REL24 local entry. An ELFv2 callee that sets up r2 has a separate
local entry point. A direct call that already shares the callee's TOC
should branch there, skipping the global-entry prologue. The offset is
encoded in the callee's
st_other(STO_PPC64_LOCAL); functions withno separate local entry (offset 0) are unaffected.
REL32 / ADDR32. 32-bit PC-relative and absolute. REL32 is what
.eh_frameis built out of, so without it nothing with exceptiontables links cleanly.
REL64. 64-bit PC-relative — same shape as REL32 but 8 bytes.
A small generic hook
Arch::local_entry_offset(st_other)is added so theREL24 path can ask the target which entry to bias the branch by; default
is 0 (no other architecture cares).