internal/ci: assume the CI machines are reasonably modern

The Namespace runners are decently new CPUs, so bumping GOAMD64
and GOARM64 past their defaults should lead to slightly faster tests.
Especially for `go test -race`, which has a build for GOAMD64=v3
which was measured to reduce the overhead of the race detector by ~15%.

Given that `go test -race ./...` is by far the slowest job step,
taking over 90s on Linux with Go 1.24.x, this seems worthwhile.

Testing for newer architectures should not mean a loss of test coverage
for the project, given that we do not write any assembly or SIMD code.
Likewise, it should not cause any changes in the build artifacts
generated by goreleaser, given that those use separate env vars.

Signed-off-by: Daniel Martí <[email protected]>
Change-Id: I9114e480bd9f773f466a776dc20210024a4efa40
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1217817
Unity-Result: CUE porcuepine <[email protected]>
Reviewed-by: Paul Jolly <[email protected]>
TryBot-Result: CUEcueckoo <[email protected]>

Author: mvdan

.github/workflows/release.yaml

@@ -62,6 +62,11 @@ jobs:
         run: |-
           go env -w GOTOOLCHAIN=local
 
+          case $(go env GOARCH) in
+          amd64) go env -w GOAMD64=v3 ;;   # 2013 and later; makes `go test -race` 15% faster
+          arm64) go env -w GOARM64=v8.6 ;; # Apple M2 and later
+          esac
+
           # Dump env for good measure
           go env
       - name: Setup qemu

.github/workflows/trybot.yaml

@@ -75,6 +75,11 @@ jobs:
         run: |-
           go env -w GOTOOLCHAIN=local
 
+          case $(go env GOARCH) in
+          amd64) go env -w GOAMD64=v3 ;;   # 2013 and later; makes `go test -race` 15% faster
+          arm64) go env -w GOARM64=v8.6 ;; # Apple M2 and later
+          esac
+
           # Dump env for good measure
           go env
       - if: matrix.runner != 'namespace-profile-windows-2022-amd64-8x16'

internal/ci/base/github.cue

@@ -57,6 +57,11 @@ installGo: {
 				run: """
 					go env -w GOTOOLCHAIN=local
 
+					case $(go env GOARCH) in
+					amd64) go env -w GOAMD64=v3 ;;   # 2013 and later; makes `go test -race` 15% faster
+					arm64) go env -w GOARM64=v8.6 ;; # Apple M2 and later
+					esac
+
 					# Dump env for good measure
 					go env
 					"""