Currently, package obj reserves a range of 1<<12 opcodes for each
target architecture. E.g., mips64 has [6<<12, 7<<12).
However, because mips.ABEQ and mips.ALAST are both within that range,
the expression mips.ABEQ+mips.ALAST in turn falls (far) outside that
range around 12<<12, meaning it could theoretically collide with
another arch's opcodes.
More practically, it's a problem because 12<<12 overflows an int16,
which hampers fixing #14692. (We could also just switch to uint16 to
avoid the overflow, but that still leaves the first problem.)
As a workaround, use Michael Hudson-Doyle's solution from
https://golang.org/cl/20182 and use negative values for these variant
instructions.
Passes toolstash -cmp for GOARCH=arm and GOARCH=mips64.
Updates #14692.
Change-Id: Iad797d10652360109fa4db19d4d1edb6529fc2c0
Reviewed-on: https://go-review.googlesource.com/20345
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
When using GOEXPERIMENT=fieldtrack, we can see AUSEFIELD instructions.
We generally want to ignore them.
No tests because as far as I can tell there are no tests for
GOEXPERIMENT=fieldtrack.
Change-Id: Iee26f25592158e5db691a36cf8d77fc54d051314
Reviewed-on: https://go-review.googlesource.com/17610
Reviewed-by: David Symonds <dsymonds@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
MIPS64 has 32 general purpose 64-bit integer registers (R0-R31), 32
64-bit floating point registers (F0-F31). Instructions are fixed-width,
and are 32-bit wide. Instructions are all in standard 1-, 2-, 3-operand
forms.
MIPS64-specific relocations are added. For this reason, test data of
cmd/newlink are regenerated.
No other changes are made to portable structures.
Branch delay slots are current filled with NOP instructions. The function
for instruction scheduling (try to fill the delay slot with a useful
instruction) is implemented but disabled for now.
Change-Id: Ic364999c7a33245260c1381fc26a2fa8972d38b3
Reviewed-on: https://go-review.googlesource.com/14442
Reviewed-by: Minux Ma <minux@golang.org>
It's particularly nice to get rid of the android special cases in the linker.
Change-Id: I516363af7ce8a6b2f196fe49cb8887ac787a6dad
Reviewed-on: https://go-review.googlesource.com/14197
Run-TryBot: Michael Hudson-Doyle <michael.hudson@canonical.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Just a mechanical copy with filename renames, no code changes.
This is to reduce code difference when adding the mips64 port.
Change-Id: Id06e975f414a7b09f4827167b30813b228a3bfae
Reviewed-on: https://go-review.googlesource.com/14323
Reviewed-by: Ian Lance Taylor <iant@golang.org>
