rtld/powerpc: Fix _rtld_bind_start for powerpcspe
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Authored by jhibbits on Nov 23 2019, 5:22 PM.

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Reviewers

nwhitehorn
bdragon
luporl

Commits

rS355045: rtld/powerpc: Fix _rtld_bind_start for powerpcspe

Summary

We need to save off the full 64-bit register, not just the low 32 bits,
of all registers getting saved off in _rtld_bind_start. Additionally,
we need to save off the other SPE registers (SPEFSCR and accumulator),
so that their program state is not affected by the PLT resolver.

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Build Status

Buildable 27730
Build 25928: arc lint + arc unit

Event Timeline

jhibbits created this revision.Nov 23 2019, 5:22 PM

Harbormaster completed remote builds in B27728: Diff 64766.Nov 23 2019, 5:22 PM

bdragon added inline comments.Nov 23 2019, 5:55 PM

libexec/rtld-elf/powerpc/rtld_start.S
114	Comment is outdated now. Maybe something like /* stack space for r0, r3-r31 and nonvolatile SPRs + callee save area */
128–131	same here. Probably don't need to duplicate the comment either since it's now obvious what it's doing.

bdragon added inline comments.Nov 23 2019, 6:32 PM

libexec/rtld-elf/powerpc/rtld_start.S
110	We're now allocating 20 bytes less stack than the original code in the !SPE case. Your math looks more correct to me though, so the original -160 must have been wrong.