go/test/codegen/fuse.go
Michael Munday 97fd6bdecc cmd/compile: fuse NaN checks with other comparisons
NaN checks can often be merged into other comparisons by inverting them.
For example, `math.IsNaN(x) || x > 0` is equivalent to `!(x <= 0)`.

goos: linux
goarch: amd64
pkg: math
cpu: 12th Gen Intel(R) Core(TM) i7-12700T
            │         sec/op         │    sec/op     vs base                │
Acos                     4.315n ± 0%    4.314n ± 0%        ~ (p=0.642 n=10)
Acosh                    8.398n ± 0%    7.779n ± 0%   -7.37% (p=0.000 n=10)
Asin                     4.203n ± 0%    4.211n ± 0%   +0.20% (p=0.001 n=10)
Asinh                   10.150n ± 0%    9.562n ± 0%   -5.79% (p=0.000 n=10)
Atan                     2.363n ± 0%    2.363n ± 0%        ~ (p=0.801 n=10)
Atanh                    8.192n ± 2%    7.685n ± 0%   -6.20% (p=0.000 n=10)
Atan2                    4.013n ± 0%    4.010n ± 0%        ~ (p=0.073 n=10)
Cbrt                     4.858n ± 0%    4.755n ± 0%   -2.12% (p=0.000 n=10)
Cos                      4.596n ± 0%    4.357n ± 0%   -5.20% (p=0.000 n=10)
Cosh                     5.071n ± 0%    5.071n ± 0%        ~ (p=0.585 n=10)
Erf                      2.802n ± 1%    2.788n ± 0%   -0.54% (p=0.002 n=10)
Erfc                     3.087n ± 1%    3.071n ± 0%        ~ (p=0.320 n=10)
Erfinv                   3.981n ± 0%    3.965n ± 0%   -0.41% (p=0.000 n=10)
Erfcinv                  3.985n ± 0%    3.977n ± 0%   -0.20% (p=0.000 n=10)
ExpGo                    8.721n ± 2%    8.252n ± 0%   -5.38% (p=0.000 n=10)
Expm1                    4.378n ± 0%    4.228n ± 0%   -3.43% (p=0.000 n=10)
Exp2                     8.313n ± 0%    7.855n ± 0%   -5.52% (p=0.000 n=10)
Exp2Go                   8.498n ± 2%    7.921n ± 0%   -6.79% (p=0.000 n=10)
Mod                      15.16n ± 4%    12.20n ± 1%  -19.58% (p=0.000 n=10)
Frexp                    1.780n ± 2%    1.496n ± 0%  -15.96% (p=0.000 n=10)
Gamma                    4.378n ± 1%    4.013n ± 0%   -8.35% (p=0.000 n=10)
HypotGo                  2.655n ± 5%    2.427n ± 1%   -8.57% (p=0.000 n=10)
Ilogb                    1.912n ± 5%    1.749n ± 0%   -8.53% (p=0.000 n=10)
J0                       22.43n ± 9%    20.46n ± 0%   -8.76% (p=0.000 n=10)
J1                       21.03n ± 4%    19.96n ± 0%   -5.09% (p=0.000 n=10)
Jn                       45.40n ± 1%    42.59n ± 0%   -6.20% (p=0.000 n=10)
Ldexp                    2.312n ± 1%    1.944n ± 0%  -15.94% (p=0.000 n=10)
Lgamma                   4.617n ± 1%    4.584n ± 0%   -0.73% (p=0.000 n=10)
Log                      4.226n ± 0%    4.213n ± 0%   -0.31% (p=0.001 n=10)
Logb                     1.771n ± 0%    1.775n ± 0%        ~ (p=0.097 n=10)
Log1p                    5.102n ± 2%    5.001n ± 0%   -1.97% (p=0.000 n=10)
Log10                    4.407n ± 0%    4.408n ± 0%        ~ (p=1.000 n=10)
Log2                     2.416n ± 1%    2.138n ± 0%  -11.51% (p=0.000 n=10)
Modf                     1.669n ± 2%    1.611n ± 0%   -3.50% (p=0.000 n=10)
Nextafter32              2.186n ± 0%    2.185n ± 0%        ~ (p=0.051 n=10)
Nextafter64              2.182n ± 0%    2.184n ± 0%   +0.09% (p=0.016 n=10)
PowInt                   11.39n ± 6%    10.68n ± 2%   -6.24% (p=0.000 n=10)
PowFrac                  26.60n ± 2%    26.12n ± 0%   -1.80% (p=0.000 n=10)
Pow10Pos                0.5067n ± 4%   0.5003n ± 1%   -1.27% (p=0.001 n=10)
Pow10Neg                0.8552n ± 0%   0.8552n ± 0%        ~ (p=0.928 n=10)
Round                    1.181n ± 0%    1.182n ± 0%   +0.08% (p=0.001 n=10)
RoundToEven              1.709n ± 0%    1.710n ± 0%        ~ (p=0.053 n=10)
Remainder                12.54n ± 5%    11.99n ± 2%   -4.46% (p=0.000 n=10)
Sin                      3.933n ± 5%    3.926n ± 0%   -0.17% (p=0.000 n=10)
Sincos                   5.672n ± 0%    5.522n ± 0%   -2.65% (p=0.000 n=10)
Sinh                     5.447n ± 1%    5.444n ± 0%   -0.06% (p=0.029 n=10)
Tan                      4.061n ± 0%    4.058n ± 0%   -0.07% (p=0.005 n=10)
Tanh                     5.599n ± 0%    5.595n ± 0%   -0.06% (p=0.042 n=10)
Y0                       20.75n ± 5%    19.73n ± 1%   -4.92% (p=0.000 n=10)
Y1                       20.87n ± 2%    19.78n ± 1%   -5.20% (p=0.000 n=10)
Yn                       44.50n ± 2%    42.04n ± 2%   -5.53% (p=0.000 n=10)
geomean                  4.989n         4.791n        -3.96%

goos: linux
goarch: riscv64
pkg: math
cpu: Spacemit(R) X60
                    │     sec/op     │    sec/op     vs base                  │
Acos                    159.9n ±  0%   159.9n ±  0%        ~ (p=0.269 n=10)
Acosh                   244.7n ±  0%   235.0n ±  0%   -3.98% (p=0.000 n=10)
Asin                    159.9n ±  0%   159.9n ±  0%        ~ (p=0.154 n=10)
Asinh                   270.8n ±  0%   261.1n ±  0%   -3.60% (p=0.000 n=10)
Atan                    119.1n ±  0%   119.1n ±  0%        ~ (p=0.347 n=10)
Atanh                   260.2n ±  0%   261.8n ±  4%        ~ (p=0.459 n=10)
Atan2                   186.8n ±  0%   186.8n ±  0%        ~ (p=0.487 n=10)
Cbrt                    203.5n ±  0%   198.2n ±  0%   -2.60% (p=0.000 n=10)
Ceil                    31.82n ±  0%   31.81n ±  0%        ~ (p=0.714 n=10)
Copysign                4.894n ±  0%   4.893n ±  0%        ~ (p=0.161 n=10)
Cos                     107.6n ±  0%   103.6n ±  0%   -3.76% (p=0.000 n=10)
Cosh                    259.0n ±  0%   252.8n ±  0%   -2.39% (p=0.000 n=10)
Erf                     133.7n ±  0%   133.7n ±  0%        ~ (p=0.720 n=10)
Erfc                    137.9n ±  0%   137.8n ±  0%   -0.04% (p=0.033 n=10)
Erfinv                  173.7n ±  0%   168.8n ±  0%   -2.82% (p=0.000 n=10)
Erfcinv                 173.7n ±  0%   168.8n ±  0%   -2.82% (p=0.000 n=10)
Exp                     215.3n ±  0%   208.1n ±  0%   -3.34% (p=0.000 n=10)
ExpGo                   226.7n ±  0%   220.6n ±  0%   -2.69% (p=0.000 n=10)
Expm1                   164.8n ±  0%   159.0n ±  0%   -3.52% (p=0.000 n=10)
Exp2                    185.0n ±  0%   182.7n ±  0%   -1.22% (p=0.000 n=10)
Exp2Go                  198.9n ±  0%   196.5n ±  0%   -1.21% (p=0.000 n=10)
Abs                     4.894n ±  0%   4.893n ±  0%        ~ (p=0.262 n=10)
Dim                     16.31n ±  0%   16.31n ±  0%        ~ (p=1.000 n=10)
Floor                   31.81n ±  0%   31.81n ±  0%        ~ (p=0.067 n=10)
Max                     26.11n ±  0%   26.10n ±  0%        ~ (p=0.080 n=10)
Min                     26.10n ±  0%   26.10n ±  0%        ~ (p=0.095 n=10)
Mod                     337.7n ±  0%   291.9n ±  0%  -13.56% (p=0.000 n=10)
Frexp                   50.57n ±  0%   42.41n ±  0%  -16.13% (p=0.000 n=10)
Gamma                   206.3n ±  0%   198.1n ±  0%   -4.00% (p=0.000 n=10)
Hypot                   94.62n ±  0%   94.61n ±  0%        ~ (p=0.437 n=10)
HypotGo                 109.3n ±  0%   109.3n ±  0%        ~ (p=1.000 n=10)
Ilogb                   44.05n ±  0%   44.04n ±  0%   -0.02% (p=0.025 n=10)
J0                      663.1n ±  0%   663.9n ±  0%   +0.13% (p=0.002 n=10)
J1                      663.9n ±  0%   666.4n ±  0%   +0.38% (p=0.000 n=10)
Jn                      1.404µ ±  0%   1.407µ ±  0%   +0.21% (p=0.000 n=10)
Ldexp                   57.10n ±  0%   48.93n ±  0%  -14.30% (p=0.000 n=10)
Lgamma                  185.1n ±  0%   187.6n ±  0%   +1.32% (p=0.000 n=10)
Log                     182.7n ±  0%   170.1n ±  0%   -6.87% (p=0.000 n=10)
Logb                    46.49n ±  0%   46.49n ±  0%        ~ (p=0.675 n=10)
Log1p                   184.3n ±  0%   179.4n ±  0%   -2.63% (p=0.000 n=10)
Log10                   184.3n ±  0%   171.2n ±  0%   -7.08% (p=0.000 n=10)
Log2                    66.05n ±  0%   57.90n ±  0%  -12.34% (p=0.000 n=10)
Modf                    34.25n ±  0%   34.24n ±  0%        ~ (p=0.163 n=10)
Nextafter32             49.33n ±  1%   48.93n ±  0%   -0.81% (p=0.002 n=10)
Nextafter64             43.64n ±  0%   43.23n ±  0%   -0.93% (p=0.000 n=10)
PowInt                  267.6n ±  0%   251.2n ±  0%   -6.11% (p=0.000 n=10)
PowFrac                 672.9n ±  0%   637.9n ±  0%   -5.19% (p=0.000 n=10)
Pow10Pos                13.87n ±  0%   13.87n ±  0%        ~ (p=1.000 n=10)
Pow10Neg                19.58n ± 62%   19.59n ± 62%        ~ (p=0.355 n=10)
Round                   23.65n ±  0%   23.65n ±  0%        ~ (p=1.000 n=10)
RoundToEven             27.73n ±  0%   27.73n ±  0%        ~ (p=0.635 n=10)
Remainder               309.9n ±  0%   280.5n ±  0%   -9.49% (p=0.000 n=10)
Signbit                 13.05n ±  0%   13.05n ±  0%        ~ (p=1.000 n=10) ¹
Sin                     120.7n ±  0%   120.7n ±  0%        ~ (p=1.000 n=10) ¹
Sincos                  148.4n ±  0%   143.5n ±  0%   -3.30% (p=0.000 n=10)
Sinh                    275.6n ±  0%   267.5n ±  0%   -2.94% (p=0.000 n=10)
SqrtIndirect            3.262n ±  0%   3.262n ±  0%        ~ (p=0.263 n=10)
SqrtLatency             19.57n ±  0%   19.57n ±  0%        ~ (p=0.582 n=10)
SqrtIndirectLatency     19.57n ±  0%   19.57n ±  0%        ~ (p=1.000 n=10)
SqrtGoLatency           203.2n ±  0%   197.6n ±  0%   -2.78% (p=0.000 n=10)
SqrtPrime               4.952µ ±  0%   4.952µ ±  0%   -0.01% (p=0.025 n=10)
Tan                     153.3n ±  0%   153.3n ±  0%        ~ (p=1.000 n=10)
Tanh                    280.5n ±  0%   272.4n ±  0%   -2.91% (p=0.000 n=10)
Trunc                   31.81n ±  0%   31.81n ±  0%        ~ (p=1.000 n=10)
Y0                      680.1n ±  0%   664.8n ±  0%   -2.25% (p=0.000 n=10)
Y1                      684.2n ±  0%   669.6n ±  0%   -2.14% (p=0.000 n=10)
Yn                      1.444µ ±  0%   1.410µ ±  0%   -2.35% (p=0.000 n=10)
Float64bits             5.709n ±  0%   5.708n ±  0%        ~ (p=0.573 n=10)
Float64frombits         4.893n ±  0%   4.893n ±  0%        ~ (p=0.734 n=10)
Float32bits             12.23n ±  0%   12.23n ±  0%        ~ (p=0.628 n=10)
Float32frombits         4.893n ±  0%   4.893n ±  0%        ~ (p=0.971 n=10)
FMA                     4.893n ±  0%   4.893n ±  0%        ~ (p=0.736 n=10)
geomean                 88.96n         87.05n         -2.15%
¹ all samples are equal

Change-Id: I8db8ac7b7b3430b946b89e88dd6c1546804125c3
Reviewed-on: https://go-review.googlesource.com/c/go/+/697360
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Keith Randall <khr@google.com>
Auto-Submit: Michael Munday <mikemndy@gmail.com>
2025-10-08 08:11:17 -07:00

298 lines
7.3 KiB
Go

// asmcheck
// Copyright 2019 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"
// Notes:
// - these examples use channels to provide a source of
// unknown values that cannot be optimized away
// - these examples use for loops to force branches
// backward (predicted taken)
// ---------------------------------- //
// signed integer range (conjunction) //
// ---------------------------------- //
func si1c(c <-chan int64) {
// amd64:"CMPQ\t.+, [$]256"
// s390x:"CLGIJ\t[$]12, R[0-9]+, [$]255"
for x := <-c; x >= 0 && x < 256; x = <-c {
}
}
func si2c(c <-chan int32) {
// amd64:"CMPL\t.+, [$]256"
// s390x:"CLIJ\t[$]12, R[0-9]+, [$]255"
for x := <-c; x >= 0 && x < 256; x = <-c {
}
}
func si3c(c <-chan int16) {
// amd64:"CMPW\t.+, [$]256"
// s390x:"CLIJ\t[$]12, R[0-9]+, [$]255"
for x := <-c; x >= 0 && x < 256; x = <-c {
}
}
func si4c(c <-chan int8) {
// amd64:"CMPB\t.+, [$]10"
// s390x:"CLIJ\t[$]4, R[0-9]+, [$]10"
for x := <-c; x >= 0 && x < 10; x = <-c {
}
}
func si5c(c <-chan int64) {
// amd64:"CMPQ\t.+, [$]251","ADDQ\t[$]-5,"
// s390x:"CLGIJ\t[$]4, R[0-9]+, [$]251","ADD\t[$]-5,"
for x := <-c; x < 256 && x > 4; x = <-c {
}
}
func si6c(c <-chan int32) {
// amd64:"CMPL\t.+, [$]255","DECL\t"
// s390x:"CLIJ\t[$]12, R[0-9]+, [$]255","ADDW\t[$]-1,"
for x := <-c; x > 0 && x <= 256; x = <-c {
}
}
func si7c(c <-chan int16) {
// amd64:"CMPW\t.+, [$]60","ADDL\t[$]10,"
// s390x:"CLIJ\t[$]12, R[0-9]+, [$]60","ADDW\t[$]10,"
for x := <-c; x >= -10 && x <= 50; x = <-c {
}
}
func si8c(c <-chan int8) {
// amd64:"CMPB\t.+, [$]126","ADDL\t[$]126,"
// s390x:"CLIJ\t[$]4, R[0-9]+, [$]126","ADDW\t[$]126,"
for x := <-c; x >= -126 && x < 0; x = <-c {
}
}
// ---------------------------------- //
// signed integer range (disjunction) //
// ---------------------------------- //
func si1d(c <-chan int64) {
// amd64:"CMPQ\t.+, [$]256"
// s390x:"CLGIJ\t[$]2, R[0-9]+, [$]255"
for x := <-c; x < 0 || x >= 256; x = <-c {
}
}
func si2d(c <-chan int32) {
// amd64:"CMPL\t.+, [$]256"
// s390x:"CLIJ\t[$]2, R[0-9]+, [$]255"
for x := <-c; x < 0 || x >= 256; x = <-c {
}
}
func si3d(c <-chan int16) {
// amd64:"CMPW\t.+, [$]256"
// s390x:"CLIJ\t[$]2, R[0-9]+, [$]255"
for x := <-c; x < 0 || x >= 256; x = <-c {
}
}
func si4d(c <-chan int8) {
// amd64:"CMPB\t.+, [$]10"
// s390x:"CLIJ\t[$]10, R[0-9]+, [$]10"
for x := <-c; x < 0 || x >= 10; x = <-c {
}
}
func si5d(c <-chan int64) {
// amd64:"CMPQ\t.+, [$]251","ADDQ\t[$]-5,"
// s390x:"CLGIJ\t[$]10, R[0-9]+, [$]251","ADD\t[$]-5,"
for x := <-c; x >= 256 || x <= 4; x = <-c {
}
}
func si6d(c <-chan int32) {
// amd64:"CMPL\t.+, [$]255","DECL\t"
// s390x:"CLIJ\t[$]2, R[0-9]+, [$]255","ADDW\t[$]-1,"
for x := <-c; x <= 0 || x > 256; x = <-c {
}
}
func si7d(c <-chan int16) {
// amd64:"CMPW\t.+, [$]60","ADDL\t[$]10,"
// s390x:"CLIJ\t[$]2, R[0-9]+, [$]60","ADDW\t[$]10,"
for x := <-c; x < -10 || x > 50; x = <-c {
}
}
func si8d(c <-chan int8) {
// amd64:"CMPB\t.+, [$]126","ADDL\t[$]126,"
// s390x:"CLIJ\t[$]10, R[0-9]+, [$]126","ADDW\t[$]126,"
for x := <-c; x < -126 || x >= 0; x = <-c {
}
}
// ------------------------------------ //
// unsigned integer range (conjunction) //
// ------------------------------------ //
func ui1c(c <-chan uint64) {
// amd64:"CMPQ\t.+, [$]251","ADDQ\t[$]-5,"
// s390x:"CLGIJ\t[$]4, R[0-9]+, [$]251","ADD\t[$]-5,"
for x := <-c; x < 256 && x > 4; x = <-c {
}
}
func ui2c(c <-chan uint32) {
// amd64:"CMPL\t.+, [$]255","DECL\t"
// s390x:"CLIJ\t[$]12, R[0-9]+, [$]255","ADDW\t[$]-1,"
for x := <-c; x > 0 && x <= 256; x = <-c {
}
}
func ui3c(c <-chan uint16) {
// amd64:"CMPW\t.+, [$]40","ADDL\t[$]-10,"
// s390x:"CLIJ\t[$]12, R[0-9]+, [$]40","ADDW\t[$]-10,"
for x := <-c; x >= 10 && x <= 50; x = <-c {
}
}
func ui4c(c <-chan uint8) {
// amd64:"CMPB\t.+, [$]2","ADDL\t[$]-126,"
// s390x:"CLIJ\t[$]4, R[0-9]+, [$]2","ADDW\t[$]-126,"
for x := <-c; x >= 126 && x < 128; x = <-c {
}
}
// ------------------------------------ //
// unsigned integer range (disjunction) //
// ------------------------------------ //
func ui1d(c <-chan uint64) {
// amd64:"CMPQ\t.+, [$]251","ADDQ\t[$]-5,"
// s390x:"CLGIJ\t[$]10, R[0-9]+, [$]251","ADD\t[$]-5,"
for x := <-c; x >= 256 || x <= 4; x = <-c {
}
}
func ui2d(c <-chan uint32) {
// amd64:"CMPL\t.+, [$]254","ADDL\t[$]-2,"
// s390x:"CLIJ\t[$]2, R[0-9]+, [$]254","ADDW\t[$]-2,"
for x := <-c; x <= 1 || x > 256; x = <-c {
}
}
func ui3d(c <-chan uint16) {
// amd64:"CMPW\t.+, [$]40","ADDL\t[$]-10,"
// s390x:"CLIJ\t[$]2, R[0-9]+, [$]40","ADDW\t[$]-10,"
for x := <-c; x < 10 || x > 50; x = <-c {
}
}
func ui4d(c <-chan uint8) {
// amd64:"CMPB\t.+, [$]2","ADDL\t[$]-126,"
// s390x:"CLIJ\t[$]10, R[0-9]+, [$]2","ADDW\t[$]-126,"
for x := <-c; x < 126 || x >= 128; x = <-c {
}
}
// -------------------------------------//
// merge NaN checks //
// ------------------------------------ //
func f64NaNOrPosInf(c <-chan float64) {
// This test assumes IsInf(x, 1) is implemented as x > MaxFloat rather than x == Inf(1).
// amd64:"JCS",-"JNE",-"JPS",-"JPC"
// riscv64:"FCLASSD",-"FLED",-"FLTD",-"FNED",-"FEQD"
for x := <-c; math.IsNaN(x) || math.IsInf(x, 1); x = <-c {
}
}
func f64NaNOrNegInf(c <-chan float64) {
// This test assumes IsInf(x, -1) is implemented as x < -MaxFloat rather than x == Inf(-1).
// amd64:"JCS",-"JNE",-"JPS",-"JPC"
// riscv64:"FCLASSD",-"FLED",-"FLTD",-"FNED",-"FEQD"
for x := <-c; math.IsNaN(x) || math.IsInf(x, -1); x = <-c {
}
}
func f64NaNOrLtOne(c <-chan float64) {
// amd64:"JCS",-"JNE",-"JPS",-"JPC"
// riscv64:"FLED",-"FLTD",-"FNED",-"FEQD"
for x := <-c; math.IsNaN(x) || x < 1; x = <-c {
}
}
func f64NaNOrLteOne(c <-chan float64) {
// amd64:"JLS",-"JNE",-"JPS",-"JPC"
// riscv64:"FLTD",-"FLED",-"FNED",-"FEQD"
for x := <-c; x <= 1 || math.IsNaN(x); x = <-c {
}
}
func f64NaNOrGtOne(c <-chan float64) {
// amd64:"JCS",-"JNE",-"JPS",-"JPC"
// riscv64:"FLED",-"FLTD",-"FNED",-"FEQD"
for x := <-c; math.IsNaN(x) || x > 1; x = <-c {
}
}
func f64NaNOrGteOne(c <-chan float64) {
// amd64:"JLS",-"JNE",-"JPS",-"JPC"
// riscv64:"FLTD",-"FLED",-"FNED",-"FEQD"
for x := <-c; x >= 1 || math.IsNaN(x); x = <-c {
}
}
func f32NaNOrLtOne(c <-chan float32) {
// amd64:"JCS",-"JNE",-"JPS",-"JPC"
// riscv64:"FLES",-"FLTS",-"FNES",-"FEQS"
for x := <-c; x < 1 || x != x; x = <-c {
}
}
func f32NaNOrLteOne(c <-chan float32) {
// amd64:"JLS",-"JNE",-"JPS",-"JPC"
// riscv64:"FLTS",-"FLES",-"FNES",-"FEQS"
for x := <-c; x != x || x <= 1; x = <-c {
}
}
func f32NaNOrGtOne(c <-chan float32) {
// amd64:"JCS",-"JNE",-"JPS",-"JPC"
// riscv64:"FLES",-"FLTS",-"FNES",-"FEQS"
for x := <-c; x > 1 || x != x; x = <-c {
}
}
func f32NaNOrGteOne(c <-chan float32) {
// amd64:"JLS",-"JNE",-"JPS",-"JPC"
// riscv64:"FLTS",-"FLES",-"FNES",-"FEQS"
for x := <-c; x != x || x >= 1; x = <-c {
}
}
// ------------------------------------ //
// regressions //
// ------------------------------------ //
func gte4(x uint64) bool {
return x >= 4
}
func lt20(x uint64) bool {
return x < 20
}
func issue74915(c <-chan uint64) {
// Check that the optimization is not blocked by function inlining.
// amd64:"CMPQ\t.+, [$]16","ADDQ\t[$]-4,"
// s390x:"CLGIJ\t[$]4, R[0-9]+, [$]16","ADD\t[$]-4,"
for x := <-c; gte4(x) && lt20(x); x = <-c {
}
}