4 Commits

Author SHA1 Message Date
Kai Nacke
427fb35192 [PPC] Opaque pointer migration, part 1.
The LIT test cases were migrated with the script provided by
Nikita Popov. Due to the size of the change it is split into
several parts.

Reviewed By: nemanja, amyk, nikic, PowerPC

Differential Revision: https://reviews.llvm.org/D135470
2022-10-11 17:24:06 +00:00
Itay Bookstein
848812a55e [Verifier] Add verification logic for GlobalIFuncs
Verify that the resolver exists, that it is a defined
Function, and that its return type matches the ifunc's
type. Add corresponding check to BitcodeReader, change
clang to emit the correct type, and fix tests to comply.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D112349
2021-10-31 20:00:57 -07:00
Stefan Pintilie
b294e00fb0 [PowerPC] Fix for PC Relative call protocol
The situation where the caller uses a TOC and the callee does not
but is marked as clobbers the TOC (st_other=1) was not being compiled
correctly if both functions where in the same object file.

The call site where we had `callee` was missing a nop after the call.
This is because it was assumed that since the two functions where in
the same DSO they would be sharing a TOC. This is not the case if the
callee uses PC Relative because in that case it may clobber the TOC.
This patch makes sure that we add the cnop correctly so that the
linker has a place to restore the TOC.

Reviewers: sfertile, NeHuang, saghir

Differential Revision: https://reviews.llvm.org/D81126
2020-07-01 07:08:41 -05:00
Fangrui Song
e8054f0933 [PPC32] Emit R_PPC_PLTREL24 for calls to dso_local ifunc
static void *ifunc(void) __attribute__((ifunc("resolver")));
  void foo() { ifunc(); }

The relocation produced by the ifunc() call:

1. gcc -msecure-plt -fPIC => R_PPC_PLTREL24 r_addend=0x8000
2. gcc -msecure-plt -PIE => R_PPC_PLTREL24 r_addend=0x8000
3. clang -msecure-plt -fPIC => R_PPC_PLTREL24 r_addend=0x8000
4. clang -msecure-plt -fPIE => R_PPC_REL24

4 is incorrect. The R_PPC_REL24 needs a call stub due to ifunc. If this
relocation is mixed with other R_PPC_PLTREL24(r_addend=0x8000) in a
function, both GNU ld and lld (after D71621 fix) may produce a wrong
result.

This patch fixes 4 to use R_PPC_PLTREL24, which matches GCC.
Both GNU ld and lld (after D71621) will be happy.

Reviewed By: sfertile

Differential Revision: https://reviews.llvm.org/D71649
2019-12-20 11:32:02 -08:00