Pushed r14-{4848..4852}.
On Thu, 2023-10-19 at 22:02 +0800, Xi Ruoyao wrote:
> For relaxation we are now generating assembler macros for symbolic
> addresses everywhere, but this is limiting scheduling and there are
> known situations where the relaxation cannot improve the code.
>
> 1. When we are performing LTO during a final link and the linker plugin
> is used, la.global won't be relaxed because they reference to an
> external or preemptable symbol.
> 2. The linker currently do not relax la.tls.*.
> 3. For la.local + ld/st pairs, if the address is only used once,
> emitting pcalau12i + ld/st is always not worse than relying on linker
> relaxation.
>
> Add -mexplicit-relocs=auto to allow the compiler to use explicit relocs
> for these cases, but assembler macros for other cases. Use it as the
> default if the assembler supports both explicit relocs and relaxation.
>
> LTO-bootstrapped and regtested on loongarch64-linux-gnu. Ok for trunk?
>
> Xi Ruoyao (5):
> LoongArch: Add enum-style -mexplicit-relocs= option
> LoongArch: Use explicit relocs for GOT access when
> -mexplicit-relocs=auto and LTO during a final link with linker
> plugin
> LoongArch: Use explicit relocs for TLS access with
> -mexplicit-relocs=auto
> LoongArch: Use explicit relocs for addresses only used for one load or
> store with -mexplicit-relocs=auto and -mcmodel={normal,medium}
> LoongArch: Document -mexplicit-relocs={auto,none,always}
>
> .../loongarch/genopts/loongarch-strings | 6 +
> gcc/config/loongarch/genopts/loongarch.opt.in | 21 ++-
> gcc/config/loongarch/loongarch-def.h | 6 +
> gcc/config/loongarch/loongarch-protos.h | 1 +
> gcc/config/loongarch/loongarch-str.h | 5 +
> gcc/config/loongarch/loongarch.cc | 75 ++++++++--
> gcc/config/loongarch/loongarch.h | 3 +
> gcc/config/loongarch/loongarch.md | 128 +++++++++++++++++-
> gcc/config/loongarch/loongarch.opt | 21 ++-
> gcc/config/loongarch/predicates.md | 15 +-
> gcc/doc/invoke.texi | 37 +++--
> .../loongarch/explicit-relocs-auto-lto.c | 26 ++++
> ...-relocs-auto-single-load-store-no-anchor.c | 6 +
> .../explicit-relocs-auto-single-load-store.c | 14 ++
> .../explicit-relocs-auto-tls-ld-gd.c | 9 ++
> .../explicit-relocs-auto-tls-le-ie.c | 6 +
> 16 files changed, 343 insertions(+), 36 deletions(-)
> create mode 100644
> gcc/testsuite/gcc.target/loongarch/explicit-relocs-auto-lto.c
> create mode 100644
> gcc/testsuite/gcc.target/loongarch/explicit-relocs-auto-single-load-store-no-anchor.c
> create mode 100644
> gcc/testsuite/gcc.target/loongarch/explicit-relocs-auto-single-load-store.c
> create mode 100644
> gcc/testsuite/gcc.target/loongarch/explicit-relocs-auto-tls-ld-gd.c
> create mode 100644
> gcc/testsuite/gcc.target/loongarch/explicit-relocs-auto-tls-le-ie.c
>
--
Xi Ruoyao <xry...@xry111.site>
School of Aerospace Science and Technology, Xidian University
