go/test/codegen/rotate.go
David Chase 4df3d0e4df cmd/compile: rescue stmt boundaries from OpArgXXXReg and OpSelectN.
Fixes this failure:
go test cmd/compile/internal/ssa -run TestStmtLines -v
=== RUN   TestStmtLines
    stmtlines_test.go:115: Saw too many (amd64, > 1%) lines without
    statement marks, total=88263, nostmt=1930
    ('-run TestStmtLines -v' lists failing lines)

The failure has two causes.

One is that the first-line adjuster in code generation was relocating
"first lines" to instructions that would either not have any code generated,
or would have the statment marker removed by a different believed-good heuristic.

The other was that statement boundaries were getting attached to register
values (that with the old ABI were loads from the stack, hence real instructions).
The register values disappear at code generation.

The fixes are to (1) note that certain instructions are not good choices for
"first value" and skip them, and (2) in an expandCalls post-pass, look for
register valued instructions and under appropriate conditions move their
statement marker to a compatible use.

Also updates TestStmtLines to always log the score, for easier comparison of
minor compiler changes.

Updates #40724.

Change-Id: I485573ce900e292d7c44574adb7629cdb4695c3f
Reviewed-on: https://go-review.googlesource.com/c/go/+/309649
Trust: David Chase <drchase@google.com>
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>
2021-04-14 18:46:08 +00:00

214 lines
4.3 KiB
Go

// asmcheck
// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package codegen
import "math/bits"
// ------------------- //
// const rotates //
// ------------------- //
func rot64(x uint64) uint64 {
var a uint64
// amd64:"ROLQ\t[$]7"
// ppc64:"ROTL\t[$]7"
// ppc64le:"ROTL\t[$]7"
a += x<<7 | x>>57
// amd64:"ROLQ\t[$]8"
// arm64:"ROR\t[$]56"
// s390x:"RISBGZ\t[$]0, [$]63, [$]8, "
// ppc64:"ROTL\t[$]8"
// ppc64le:"ROTL\t[$]8"
a += x<<8 + x>>56
// amd64:"ROLQ\t[$]9"
// arm64:"ROR\t[$]55"
// s390x:"RISBGZ\t[$]0, [$]63, [$]9, "
// ppc64:"ROTL\t[$]9"
// ppc64le:"ROTL\t[$]9"
a += x<<9 ^ x>>55
// s390x:"RISBGZ\t[$]0, [$]63, [$]7, "
// arm64:"ROR\t[$]57" // TODO this is not great line numbering, but then again, the instruction did appear
return a
}
func rot32(x uint32) uint32 {
var a uint32
// amd64:"ROLL\t[$]7"
// arm:"MOVW\tR\\d+@>25"
// ppc64:"ROTLW\t[$]7"
// ppc64le:"ROTLW\t[$]7"
a += x<<7 | x>>25
// amd64:`ROLL\t[$]8`
// arm:"MOVW\tR\\d+@>24"
// arm64:"RORW\t[$]24"
// s390x:"RLL\t[$]8"
// ppc64:"ROTLW\t[$]8"
// ppc64le:"ROTLW\t[$]8"
a += x<<8 + x>>24
// amd64:"ROLL\t[$]9"
// arm:"MOVW\tR\\d+@>23"
// arm64:"RORW\t[$]23"
// s390x:"RLL\t[$]9"
// ppc64:"ROTLW\t[$]9"
// ppc64le:"ROTLW\t[$]9"
a += x<<9 ^ x>>23
// s390x:"RLL\t[$]7"
// arm64:"RORW\t[$]25" // TODO this is not great line numbering, but then again, the instruction did appear
return a
}
func rot16(x uint16) uint16 {
var a uint16
// amd64:"ROLW\t[$]7"
a += x<<7 | x>>9
// amd64:`ROLW\t[$]8`
a += x<<8 + x>>8
// amd64:"ROLW\t[$]9"
a += x<<9 ^ x>>7
return a
}
func rot8(x uint8) uint8 {
var a uint8
// amd64:"ROLB\t[$]5"
a += x<<5 | x>>3
// amd64:`ROLB\t[$]6`
a += x<<6 + x>>2
// amd64:"ROLB\t[$]7"
a += x<<7 ^ x>>1
return a
}
// ----------------------- //
// non-const rotates //
// ----------------------- //
func rot64nc(x uint64, z uint) uint64 {
var a uint64
z &= 63
// amd64:"ROLQ"
// ppc64:"ROTL"
// ppc64le:"ROTL"
a += x<<z | x>>(64-z)
// amd64:"RORQ"
a += x>>z | x<<(64-z)
return a
}
func rot32nc(x uint32, z uint) uint32 {
var a uint32
z &= 31
// amd64:"ROLL"
// ppc64:"ROTLW"
// ppc64le:"ROTLW"
a += x<<z | x>>(32-z)
// amd64:"RORL"
a += x>>z | x<<(32-z)
return a
}
func rot16nc(x uint16, z uint) uint16 {
var a uint16
z &= 15
// amd64:"ROLW"
a += x<<z | x>>(16-z)
// amd64:"RORW"
a += x>>z | x<<(16-z)
return a
}
func rot8nc(x uint8, z uint) uint8 {
var a uint8
z &= 7
// amd64:"ROLB"
a += x<<z | x>>(8-z)
// amd64:"RORB"
a += x>>z | x<<(8-z)
return a
}
// Issue 18254: rotate after inlining
func f32(x uint32) uint32 {
// amd64:"ROLL\t[$]7"
return rot32nc(x, 7)
}
// --------------------------------------- //
// Combined Rotate + Masking operations //
// --------------------------------------- //
func checkMaskedRotate32(a []uint32, r int) {
i := 0
// ppc64le: "RLWNM\t[$]16, R[0-9]+, [$]8, [$]15, R[0-9]+"
// ppc64: "RLWNM\t[$]16, R[0-9]+, [$]8, [$]15, R[0-9]+"
a[i] = bits.RotateLeft32(a[i], 16) & 0xFF0000
i++
// ppc64le: "RLWNM\t[$]16, R[0-9]+, [$]8, [$]15, R[0-9]+"
// ppc64: "RLWNM\t[$]16, R[0-9]+, [$]8, [$]15, R[0-9]+"
a[i] = bits.RotateLeft32(a[i]&0xFF, 16)
i++
// ppc64le: "RLWNM\t[$]4, R[0-9]+, [$]20, [$]27, R[0-9]+"
// ppc64: "RLWNM\t[$]4, R[0-9]+, [$]20, [$]27, R[0-9]+"
a[i] = bits.RotateLeft32(a[i], 4) & 0xFF0
i++
// ppc64le: "RLWNM\t[$]16, R[0-9]+, [$]24, [$]31, R[0-9]+"
// ppc64: "RLWNM\t[$]16, R[0-9]+, [$]24, [$]31, R[0-9]+"
a[i] = bits.RotateLeft32(a[i]&0xFF0000, 16)
i++
// ppc64le: "RLWNM\tR[0-9]+, R[0-9]+, [$]8, [$]15, R[0-9]+"
// ppc64: "RLWNM\tR[0-9]+, R[0-9]+, [$]8, [$]15, R[0-9]+"
a[i] = bits.RotateLeft32(a[i], r) & 0xFF0000
i++
// ppc64le: "RLWNM\tR[0-9]+, R[0-9]+, [$]16, [$]23, R[0-9]+"
// ppc64: "RLWNM\tR[0-9]+, R[0-9]+, [$]16, [$]23, R[0-9]+"
a[i] = bits.RotateLeft32(a[3], r) & 0xFF00
i++
// ppc64le: "RLWNM\tR[0-9]+, R[0-9]+, [$]20, [$]11, R[0-9]+"
// ppc64: "RLWNM\tR[0-9]+, R[0-9]+, [$]20, [$]11, R[0-9]+"
a[i] = bits.RotateLeft32(a[3], r) & 0xFFF00FFF
i++
// ppc64le: "RLWNM\t[$]4, R[0-9]+, [$]20, [$]11, R[0-9]+"
// ppc64: "RLWNM\t[$]4, R[0-9]+, [$]20, [$]11, R[0-9]+"
a[i] = bits.RotateLeft32(a[3], 4) & 0xFFF00FFF
i++
}