Implement multi-control branches for riscv64, switching to using the BNEZ
pseudo-instruction when rewriting conditionals. This will allow for further
branch optimisations to later be performed via rewrites.
Change-Id: I7f2c69f3c77494b403f26058c6bc8432d8070ad0
Reviewed-on: https://go-review.googlesource.com/c/go/+/226399
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Joel Sing <joel@sing.id.au>
Where possible, fold constants into versions of instructions that take
an immediate. This avoids the need to allocate a register and load the
immediate into it.
Change-Id: If911ca41235e218490679aed2ce5f48bf807a2b3
Reviewed-on: https://go-review.googlesource.com/c/go/+/222639
Run-TryBot: Joel Sing <joel@sing.id.au>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
Also rewrite subtraction of zero to NEG/NEGW.
Change-Id: I216e286d1860055f2a07fe2f772cd50f366ea097
Reviewed-on: https://go-review.googlesource.com/c/go/+/221691
Reviewed-by: Cherry Zhang <cherryyz@google.com>
This allows for zero stores to be performed using the zero register, rather
than loading a separate register with zero.
Change-Id: Ic81d8dbcdacbb2ca2c3f77682ff5ad7cdc33d18d
Reviewed-on: https://go-review.googlesource.com/c/go/+/221684
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
SignExt32to64 can be implemented with a single ADDIW instruction, rather than
the two shifts that are in use currently.
Change-Id: Ie1bbaef4018f1ba5162773fc64fa5a887457cfc9
Reviewed-on: https://go-review.googlesource.com/c/go/+/220922
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Use SUBW to perform a 32-bit subtraction, rather than zero extending from
32 to 64 bits. This reduces Eq32 and Neq32 to two instructions, rather than
the four instructions required previously.
Change-Id: Ib2798324881e9db842c864e91a0c1b1e48c4b67b
Reviewed-on: https://go-review.googlesource.com/c/go/+/220921
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Duplicate the register definitions and names to avoid importing the
cmd/internal/obj/riscv64 package. This makes it possible to build compiler rules
with a stable Go tool chain.
Fixes#36663
Change-Id: I09116a97bb037ca1bc00073306a82bb88862b1e9
Reviewed-on: https://go-review.googlesource.com/c/go/+/216518
Reviewed-by: Cherry Zhang <cherryyz@google.com>
Based on riscv-go port.
Updates #27532
Change-Id: Ia329daa243db63ff334053b8807ea96b97ce3acf
Reviewed-on: https://go-review.googlesource.com/c/go/+/204631
Run-TryBot: Joel Sing <joel@sing.id.au>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Keith Randall <khr@golang.org>
