delta/go-git.git/src/cmd/internal/objabi/path.go, branch dev.cmdgo

syscall, etc.: use abi.FuncPCABI0 for libc syscall wrappers

2021-04-26T15:52:34+00:00

In CL 288092 we made Darwin syscall wrappers as ABIInternal, so
their addresses taken from Go using funcPC are the actual function
entries, not the wrappers.

As we introduced internal/abi.FuncPCABIxxx intrinsics, use that.
And change the assembly functions back to ABI0.

Do it on OpenBSD as well, as OpenBSD and Darwin share code
generator.

Change-Id: I408120795f7fc826637c867394248f8f373906bd
Reviewed-on: https://go-review.googlesource.com/c/go/+/313230
Trust: Cherry Zhang 
Run-TryBot: Cherry Zhang 
TryBot-Result: Go Bot 
Reviewed-by: Than McIntosh 
Reviewed-by: Michael Knyszek

internal/bytealg: port more performance-critical functions to ABIInternal

2021-04-15T04:10:33+00:00

CL 308931 ported several runtime assembly functions to ABIInternal so
that compiler-generated ABIInternal calls don't go through ABI
wrappers, but it missed the runtime assembly functions that are
actually defined in internal/bytealg.

This eliminates the cost of wrappers for the BleveQuery and
GopherLuaKNucleotide benchmarks, but there's still more to do for
Tile38.

                                      0-base                1-wrappers
                                     sec/op        sec/op            vs base
BleveQuery                          6.507 ± 0%    6.477 ± 0%  -0.46% (p=0.004 n=20)
GopherLuaKNucleotide                30.39 ± 1%    30.34 ± 0%       ~ (p=0.301 n=20)
Tile38IntersectsCircle100kmRequest 1.038m ± 1%   1.080m ± 2%  +4.03% (p=0.000 n=20)

For #40724.

Change-Id: I0b722443f684fcb997b1d70802c5ed4b8d8f9829
Reviewed-on: https://go-review.googlesource.com/c/go/+/310184
Trust: Austin Clements 
Reviewed-by: Michael Knyszek 
Reviewed-by: Cherry Zhang

[dev.regabi] runtime, syscall, etc.: mark Darwin syscall wrappers as ABIInternal

2021-02-03T22:43:42+00:00

Mark the syscall wrappers as ABIInternal, as they have addresses
taken from Go code, and it is important to call to them without
wrappers.

Previously, the wrapper is just a single JMP instruction, which
makes it not matter. In the next CL we'll make the wrapper
actually have a frame. The real wrappers will mess up things
such as stack alignment for C ABI.

This doesn't look really nice, but I don't know how we can do
better...

TODO: other OSes.

Change-Id: Ifb3920494990a7775e3e6902fbcaf137df3cc653
Reviewed-on: https://go-review.googlesource.com/c/go/+/288092
Trust: Cherry Zhang 
Run-TryBot: Cherry Zhang 
TryBot-Result: Go Bot 
Reviewed-by: Than McIntosh

cmd/asm: allow def/ref of func ABI when compiling runtime

2020-10-19T11:25:35+00:00

Function symbols defined and referenced by assembly source currently
always default to ABI0; this patch adds preliminary support for
accepting an explicit ABI selector clause for func defs/refs. This
functionality is currently only enabled when compiling runtime-related
packages (runtime, syscall, reflect). Examples:

  TEXT ·DefinedAbi0Symbol(SB),NOSPLIT,$0
        RET

  TEXT ·DefinedAbi1Symbol(SB),NOSPLIT,$0
        CALL    ·AbiZerolSym(SB)
	...
        JMP     ·AbiInternalSym(SB)
        RET

Also included is a small change to the code in the compiler that reads
the symabis file emitted by the assembler.

New behavior is currently gated under GOEXPERIMENT=regabi.

Updates #27539, #40724.

Change-Id: Ia22221fe26df0fa002191cfb13bdfaaa38d7df38
Reviewed-on: https://go-review.googlesource.com/c/go/+/260477
Run-TryBot: Than McIntosh 
TryBot-Result: Go Bot 
Reviewed-by: Cherry Zhang 
Trust: Than McIntosh

cmd/internal: remove duplicate pathToPrefix function

2017-04-19T11:47:45+00:00

goobj.importPathToPrefix is 3x faster than gc.pathToPrefix so rename and
move it to cmd/internal/objabi which is already imported by both goobj and
gc.

Change-Id: I10eda5bce95ef6d5d888818c5c47258c2833ea45
Reviewed-on: https://go-review.googlesource.com/40875
Run-TryBot: Todd Neal 
TryBot-Result: Gobot Gobot 
Reviewed-by: Matthew Dempsky