From 4598a8d3651b3543ea323b9fc6bf8dd954dc3a5d Mon Sep 17 00:00:00 2001 From: thesyncim Date: Sat, 31 Oct 2026 19:08:12 +0000 Subject: [PATCH 1/4] ci: install qemu-user on ubuntu-26.04 runners ubuntu-latest is now ubuntu-26.04, which has no qemu-user-static package, so every run fails at the install step and skips the arm64 tsvc run, the golden check, fmt and lint. qemu-user ships the static emulators there; link qemu-aarch64-static to it when the name is missing, as the Makefile runs that name. --- .github/workflows/test.yml | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml index ba31cc9..efe0baa 100644 --- a/.github/workflows/test.yml +++ b/.github/workflows/test.yml @@ -61,8 +61,13 @@ jobs: - name: Test tsvc (amd64, SIMD) run: make tsvc-test - - name: Install qemu-user-static - run: sudo apt-get update && sudo apt-get install -y qemu-user-static + # ubuntu-26.04 has no qemu-user-static: qemu-user ships the static + # emulators there, without the -static names the Makefile runs. + - name: Install qemu-user + run: | + sudo apt-get update && sudo apt-get install -y qemu-user + command -v qemu-aarch64-static || sudo ln -s "$(command -v qemu-aarch64)" /usr/local/bin/qemu-aarch64-static + qemu-aarch64-static --version - name: Test tsvc (arm64, qemu) run: make tsvc-test-qemu-arm64 From c5557360f5e080f9bdf5ca1c52272089b81b61dd Mon Sep 17 00:00:00 2001 From: thesyncim Date: Sat, 31 Oct 2026 20:49:40 +0000 Subject: [PATCH 2/4] go.mod: update golang.org/x/tools to read Go tip's export data Go tip writes export data in iexport version 4, which encodes float constants exactly. x/tools v0.51.0, and the v0.52.0 release, read only up to version 3, so on tip go/packages fails for every package: cannot import "math" (unstable iexport format version 4, just rebuild compiler and std library), export data is newer version - update tool and every script that runs loopvec fails in the tip job. x/tools master reads version 4 (golang/tools@966056e2637c). Update to it until a release includes it. The pinned toolchain is unaffected. --- go.mod | 10 +++++----- go.sum | 24 ++++++++++++------------ 2 files changed, 17 insertions(+), 17 deletions(-) diff --git a/go.mod b/go.mod index ed04302..9457290 100644 --- a/go.mod +++ b/go.mod @@ -3,7 +3,7 @@ module github.com/mauri870/loopvec go 1.27.1 require ( - golang.org/x/tools v0.51.0 + golang.org/x/tools v0.52.1-0.20261030190145-0f433775b36d rsc.io/script v0.0.2 ) @@ -207,10 +207,10 @@ require ( go.uber.org/zap v1.27.0 // indirect go.yaml.in/yaml/v3 v3.0.5 // indirect golang.org/x/exp/typeparams v0.0.0-20260811152304-ee035b5b010f // indirect - golang.org/x/mod v0.41.0 // indirect - golang.org/x/sync v0.23.0 // indirect - golang.org/x/sys v0.48.0 // indirect - golang.org/x/telemetry v0.0.0-20260924152758-ed294f943157 // indirect + golang.org/x/mod v0.42.0 // indirect + golang.org/x/sync v0.24.0 // indirect + golang.org/x/sys v0.49.0 // indirect + golang.org/x/telemetry v0.0.0-20261009151841-97e8ea77aa2a // indirect golang.org/x/text v0.41.0 // indirect google.golang.org/protobuf v1.36.12 // indirect gopkg.in/ini.v1 v1.67.0 // indirect diff --git a/go.sum b/go.sum index 04c2946..bb2b241 100644 --- a/go.sum +++ b/go.sum @@ -688,8 +688,8 @@ golang.org/x/mod v0.4.1/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA= golang.org/x/mod v0.6.0-dev.0.20220106191415-9b9b3d81d5e3/go.mod h1:3p9vT2HGsQu2K1YbXdKPJLVgG5VJdoTa1poYQBtP1AY= golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4= golang.org/x/mod v0.8.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs= -golang.org/x/mod v0.41.0 h1:qJmnOUb4YB+FsEuM3HcWucdZASCPGhsX6uljO6pog0c= -golang.org/x/mod v0.41.0/go.mod h1:Ek9pY8RKWXwsWvd3rQiHYtMqkjSUV+s1Rj7j4H5Ur6o= +golang.org/x/mod v0.42.0 h1:ICeL3t2L30ljSPHHxDnR4fqVcBt/zR2zJAb9juavmQg= +golang.org/x/mod v0.42.0/go.mod h1:u5fzIrRInkL8MaO1cbRkUHT64v303YIT5KEqpNr7jRs= golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4= golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4= golang.org/x/net v0.0.0-20181114220301-adae6a3d119a/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4= @@ -724,8 +724,8 @@ golang.org/x/net v0.0.0-20210525063256-abc453219eb5/go.mod h1:9nx3DQGgdP8bBQD5qx golang.org/x/net v0.0.0-20211015210444-4f30a5c0130f/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y= golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c= golang.org/x/net v0.6.0/go.mod h1:2Tu9+aMcznHK/AK1HMvgo6xiTLG5rD5rZLDS+rp2Bjs= -golang.org/x/net v0.59.0 h1:5zfYln+w5XCxwrnMMJPufRgNoXEaGxl0wo5GqPXyues= -golang.org/x/net v0.59.0/go.mod h1:2DA/G1UfVbCpQPeWTmMPGY7Cs2PkBkwu743bVX5PIVg= +golang.org/x/net v0.61.0 h1:RR+6j/BTBCrggOLugxa+66R8FvoN6MHlzDlZIbN9YFw= +golang.org/x/net v0.61.0/go.mod h1:WgDCOTH8iwtB66T4/GfI94AHo/hhdb7Hah9NDseQfiI= golang.org/x/oauth2 v0.0.0-20180821212333-d2e6202438be/go.mod h1:N/0e6XlmueqKjAGxoOufVs8QHGRruUQn6yWY3a++T0U= golang.org/x/oauth2 v0.0.0-20190226205417-e64efc72b421/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw= golang.org/x/oauth2 v0.0.0-20190604053449-0f29369cfe45/go.mod h1:gOpvHmFTYa4IltrdGE7lF6nIHvwfUNPOp7c8zoXwtLw= @@ -745,8 +745,8 @@ golang.org/x/sync v0.0.0-20201207232520-09787c993a3a/go.mod h1:RxMgew5VJxzue5/jJ golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM= golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM= golang.org/x/sync v0.1.0/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM= -golang.org/x/sync v0.23.0 h1:KameEIfc1IkluZyXWLn39Wd4tURc6GbCiISGiZm2bQk= -golang.org/x/sync v0.23.0/go.mod h1:sUUOizhqBxiL6pEWpqNLUiaJn1ShEbZ6BBqskPbjZm0= +golang.org/x/sync v0.24.0 h1:iqiDrGoDgyuvAKrhLQthUEzU/R378N78gXbBjxed7oA= +golang.org/x/sync v0.24.0/go.mod h1:sUUOizhqBxiL6pEWpqNLUiaJn1ShEbZ6BBqskPbjZm0= golang.org/x/sys v0.0.0-20180830151530-49385e6e1522/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY= golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY= golang.org/x/sys v0.0.0-20181116152217-5ac8a444bdc5/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY= @@ -790,10 +790,10 @@ golang.org/x/sys v0.0.0-20220114195835-da31bd327af9/go.mod h1:oPkhp1MJrh7nUepCBc golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg= golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg= golang.org/x/sys v0.5.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg= -golang.org/x/sys v0.48.0 h1:bbX/i/6MgT9BVLM9RT1thmxL04yeTAhbEz4SyadbXoo= -golang.org/x/sys v0.48.0/go.mod h1:hNLxWAXmnKAxqDtdwIYC4bM9oQPEecfsnNMuSxOs3og= -golang.org/x/telemetry v0.0.0-20260924152758-ed294f943157 h1:DftxASHKl6JolFPqoN+2WrFO53JvkHwRXvFqf8gsivA= -golang.org/x/telemetry v0.0.0-20260924152758-ed294f943157/go.mod h1:i+ivNqjDnTF3WTElsdk5g9V5DTSBYgdNo7xTU9SDwYA= +golang.org/x/sys v0.49.0 h1:XbzkgYJHdqh/8m2Uu0W/dQv8nktxx4BFHp1M0gROTXA= +golang.org/x/sys v0.49.0/go.mod h1:hNLxWAXmnKAxqDtdwIYC4bM9oQPEecfsnNMuSxOs3og= +golang.org/x/telemetry v0.0.0-20261009151841-97e8ea77aa2a h1:wnveMBKHwx8/nIb8WYT5P9vtefdXOvIWxzycCkc5n6Q= +golang.org/x/telemetry v0.0.0-20261009151841-97e8ea77aa2a/go.mod h1:i+ivNqjDnTF3WTElsdk5g9V5DTSBYgdNo7xTU9SDwYA= golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo= golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8= golang.org/x/term v0.5.0/go.mod h1:jMB1sMXY+tzblOD4FWmEbocvup2/aLOaQEp7JmGp78k= @@ -857,8 +857,8 @@ golang.org/x/tools v0.1.1-0.20210302220138-2ac05c832e1a/go.mod h1:9bzcO0MWcOuT0t golang.org/x/tools v0.1.10/go.mod h1:Uh6Zz+xoGYZom868N8YTex3t7RhtHDBrE8Gzo9bV56E= golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc= golang.org/x/tools v0.6.0/go.mod h1:Xwgl3UAJ/d3gWutnCtw505GrjyAbvKui8lOU390QaIU= -golang.org/x/tools v0.51.0 h1:k4Xc/1Om9jwkBJBo4NVLMSARBoWtK10mx+W5BnXCeAI= -golang.org/x/tools v0.51.0/go.mod h1:9eEncMayCV6zRMGhR5eZEC2iBx98qWcF1HZ9Z7wJOoA= +golang.org/x/tools v0.52.1-0.20261030190145-0f433775b36d h1:F5ot9G6RM6pgx3TTdKF6IZa2nocit4tcsrVQlq4Zh5w= +golang.org/x/tools v0.52.1-0.20261030190145-0f433775b36d/go.mod h1:ItcP5UNaVGG+Yc4eIYmaFLNJ4soEopkx5Y2d4lcEurs= golang.org/x/tools/go/expect v0.1.1-deprecated h1:jpBZDwmgPhXsKZC6WhL20P4b/wmnpsEAGHaNy0n/rJM= golang.org/x/tools/go/expect v0.1.1-deprecated/go.mod h1:eihoPOH+FgIqa3FpoTwguz/bVUSGBlGQU67vpBeOrBY= golang.org/x/tools/go/packages/packagestest v0.1.1-deprecated h1:1h2MnaIAIXISqTFKdENegdpAgUXz6NrPEsbIeWaBRvM= From 808d0ec4dfb3fa2b94f079c1002d1a7b07efacd1 Mon Sep 17 00:00:00 2001 From: thesyncim Date: Sat, 31 Oct 2026 21:29:58 +0000 Subject: [PATCH 3/4] Makefile: test against go1.27.3 go1.27.3 is the latest 1.27 release. Its simd package is the same as go1.27.1's, so the capability table only changes in its header, and the -methods crash (golang/go#80657) is still there, as flag_methods_ice.txt checks. go.mod keeps go 1.27.1: that is the first release whose simd package loopvec's output compiles against (go1.27.0's ShiftAllRight takes a uint8). --- BUGS.md | 6 +++--- Makefile | 2 +- internal/loopir/caps_gen.go | 2 +- 3 files changed, 5 insertions(+), 5 deletions(-) diff --git a/BUGS.md b/BUGS.md index 843087e..55231c5 100644 --- a/BUGS.md +++ b/BUGS.md @@ -2,11 +2,11 @@ loopvec rewrites code to use `GOEXPERIMENT=simd`, which is new, so most of what it hits is in the Go toolchain. This file lists the Go issues that affect loopvec. "tip" means -gotip, "1.27.1" is the release toolchain loopvec is tested against. +gotip, "1.27.3" is the release toolchain loopvec is tested against. | Issue | Status | Affects | loopvec's answer | |---|---|---|---| -| [#80657](https://github.com/golang/go/issues/80657) simd in a method: internal compiler error | fixed on tip (CL 839405), still crashes on 1.27.1 | `-methods` | methods are skipped unless `-methods` is passed | +| [#80657](https://github.com/golang/go/issues/80657) simd in a method: internal compiler error | fixed on tip (CL 839405), still crashes on 1.27.3 | `-methods` | methods are skipped unless `-methods` is passed | | [#80835](https://github.com/golang/go/issues/80835) legacy SSE encodings in functions using simd cause AVX-SSE transition penalties | open, fix pending (CLs 825145, 825146, in tip) | speed of any scalar float code that runs after a rewritten loop, in the same function or another | none; the portable `simd` package has no `ClearAVXUpperBits` | | [#81844](https://github.com/golang/go/issues/81844) blank identifier parameters rejected | fixed on tip (CL 841145) | every rewrite of a function with a `_` parameter | the generated file renames them `_p0`, `_p1`, ... | | [#81845](https://github.com/golang/go/issues/81845) calls left unresolved when inlined into a package initializer | closed as a duplicate of [#80689](https://github.com/golang/go/issues/80689), which is open | loops in package-level `var x = func() {...}()` | not rewritten (the generated initializer fails to link), see `package_initializer_no_rewrite.txt` and `toolexec_package_initializer.txt` | @@ -19,7 +19,7 @@ gotip, "1.27.1" is the release toolchain loopvec is tested against. A function with a receiver that contains simd code failed to compile with `internal compiler error: missing Types entry`. loopvec does not rewrite loops in methods -by default; `-methods` turns it on. The fix is on tip. On 1.27.1 the crash is still there, +by default; `-methods` turns it on. The fix is on tip. On 1.27.3 the crash is still there, and `flag_methods_ice.txt` pins it, so that test starts failing when the pinned toolchain gets the fix. Reported by someone else; the fix is [CL 839405](https://go.dev/cl/839405). diff --git a/Makefile b/Makefile index b4226b3..3804653 100644 --- a/Makefile +++ b/Makefile @@ -1,4 +1,4 @@ -export GOTOOLCHAIN ?= go1.27.1 +export GOTOOLCHAIN ?= go1.27.3 .DEFAULT_GOAL := build diff --git a/internal/loopir/caps_gen.go b/internal/loopir/caps_gen.go index bccacfa..ba7ddff 100644 --- a/internal/loopir/caps_gen.go +++ b/internal/loopir/caps_gen.go @@ -1,4 +1,4 @@ -// Code generated by capsgen from the simd package of go1.27.1. DO NOT EDIT. +// Code generated by capsgen from the simd package of go1.27.3. DO NOT EDIT. package loopir From 6a5db5b6d1afc20659caf7b871291d710b7315a7 Mon Sep 17 00:00:00 2001 From: thesyncim Date: Sat, 31 Oct 2026 22:26:30 +0000 Subject: [PATCH 4/4] cmd/loopvec-toolexec: give the same archive on every build The wrapper wrote the rewritten files to a new os.MkdirTemp directory under the go command's work directory. The compiler records file names in the export data, and the go command trims only the compile's own object directory, so every build of a rewritten package produced a different archive, with a random absolute path in it. That fails builds where the go command compiles a package twice with the same inputs. With PGO, go test can compile a dependency once for each test binary that needs it, then compile an importer against one copy and link the other. In github.com/thesyncim/goav1, whose cmd/qualitybench has a default.pgo, go test ./... fails with: link: fingerprint mismatch: github.com/thesyncim/goav1 has 9bcecb47ca806e38, import from github.com/thesyncim/goav1/cmd/qualitybench expecting 224b81cee36e8b4e The rewritten files now go in a loopvec directory inside the object directory, next to the importcfg the go command writes there. That is still a separate place for each compile, and the -trimpath the go command passes reduces it to loopvec/x.go. --- cmd/loopvec-toolexec/compile.go | 15 +++++++++++---- testdata/toolexec_reproducible.txt | 28 ++++++++++++++++++++++++++++ 2 files changed, 39 insertions(+), 4 deletions(-) create mode 100644 testdata/toolexec_reproducible.txt diff --git a/cmd/loopvec-toolexec/compile.go b/cmd/loopvec-toolexec/compile.go index 13f0d91..adf3ea4 100644 --- a/cmd/loopvec-toolexec/compile.go +++ b/cmd/loopvec-toolexec/compile.go @@ -197,10 +197,17 @@ func tryRewrite(tool string, args []string) (out []string, ok bool) { return nil, false } - // A package and its test variant are compiled concurrently under the same - // import path, so every compile gets its own directory. - dir, err := os.MkdirTemp(b.dir, strings.NewReplacer("/", "_", ".", "_").Replace(c.pkg)+"-") - if err != nil { + // The rewritten files go in the compile's own object directory, where the + // go command writes the importcfg: a package and its test variant are + // compiled concurrently under the same import path, so each needs its own + // place, and the go command trims that directory from file names with + // -trimpath. The file names end up in the export data, so the archive must + // not depend on where the directory is: the go command can compile a + // package twice in one build (with PGO, once for each test binary) and use + // one archive to compile its importers and the other to link them, and the + // linker rejects two archives that differ. + dir := filepath.Join(filepath.Dir(args[c.importcfg]), "loopvec") + if err := os.MkdirAll(dir, 0o755); err != nil { return nil, false } newArgs := append([]string(nil), args...) diff --git a/testdata/toolexec_reproducible.txt b/testdata/toolexec_reproducible.txt new file mode 100644 index 0000000..ad9e082 --- /dev/null +++ b/testdata/toolexec_reproducible.txt @@ -0,0 +1,28 @@ +# The wrapper compiles rewritten files from a directory of its own, and their +# names end up in the export data. Building the same package twice must still +# give the same archive: the go command can compile a package twice in one build +# (with PGO, once for each test binary that needs it), compile its importers +# against one copy and link the other, and the linker rejects two copies that +# differ. + +env GOEXPERIMENT=simd +env LOOPVEC_TOOLEXEC_LOG=$WORK/log +env GOCACHE=$WORK/gocache1 +exec go build -buildmode=archive -toolexec=$LOOPVEC_TOOLEXEC -o a1.a . +env GOCACHE=$WORK/gocache2 +exec go build -buildmode=archive -toolexec=$LOOPVEC_TOOLEXEC -o a2.a . +grep -count=2 '^rewrote 1 loop\(s\) in example\.com/lib$' log +cmp a1.a a2.a + +-- go.mod -- +module example.com/lib + +go 1.27.1 +-- lib.go -- +package lib + +func Add(dst, a, b []float32) { + for i := range dst { + dst[i] = a[i] + b[i] + } +}