cmd/go: add rva23u64 as a valid value for GORISCV64

The RVA23 profile was ratified on the 21st of October 2024.

https://riscv.org/announcements/2024/10/risc-v-announces-ratification-of-the-rva23-profile-standard/

Now that it's ratified we can add rva23u64 as a valid value for the
GORISCV64 environment variable. This will allow the compiler and
assembler to generate instructions made mandatory by the new profile
without a runtime check.  Examples of such instructions include those
introduced by the Vector and Zicond extensions.

Setting GORISCV64=rva23u64 defines the riscv64.rva20u64,
riscv64.rva22u64 and riscv64.rva23u64 build tags, sets the internal
variable buildcfg.GORISCV64 to 23 and defines the macros
GORISCV64_rva23u64, hasV, hasZba, hasZbb, hasZbs, hasZfa, and
hasZicond for use in assembly language code.

Updates #61476

Change-Id: I7641c23084fa52891c9a18df58f4013cb6597d88
Reviewed-on: https://go-review.googlesource.com/c/go/+/633417
Reviewed-by: Carlos Amedee <carlos@golang.org>
Reviewed-by: Jorropo <jorropo.pgm@gmail.com>
Reviewed-by: Joel Sing <joel@sing.id.au>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Meng Zhuo <mengzhuo1203@gmail.com>

src/cmd/go/alldocs.go

@@ -2100,8 +2100,8 @@
 //     (or ppc64le.power8, ppc64le.power9, and ppc64le.power10)
 //     feature build tags.
 //   - For GOARCH=riscv64,
-//     GORISCV64=rva20u64 and rva22u64 correspond to the riscv64.rva20u64
-//     and riscv64.rva22u64 build tags.
+//     GORISCV64=rva20u64, rva22u64 and rva23u64 correspond to the riscv64.rva20u64,
+//     riscv64.rva22u64 and riscv64.rva23u64 build tags.
 //   - For GOARCH=wasm, GOWASM=satconv and signext
 //     correspond to the wasm.satconv and wasm.signext feature build tags.
 //
@@ -2473,8 +2473,9 @@
 //		Valid values are power8 (default), power9, power10.
 //	GORISCV64
 //		For GOARCH=riscv64, the RISC-V user-mode application profile for which
-//		to compile. Valid values are rva20u64 (default), rva22u64.
+//		to compile. Valid values are rva20u64 (default), rva22u64, rva23u64.
 //		See https://github.com/riscv/riscv-profiles/blob/main/src/profiles.adoc
+//		and https://github.com/riscv/riscv-profiles/blob/main/src/rva23-profile.adoc
 //	GOWASM
 //		For GOARCH=wasm, comma-separated list of experimental WebAssembly features to use.
 //		Valid values are satconv, signext.

src/cmd/go/internal/help/helpdoc.go

@@ -646,8 +646,9 @@ Architecture-specific environment variables:
 		Valid values are power8 (default), power9, power10.
 	GORISCV64
 		For GOARCH=riscv64, the RISC-V user-mode application profile for which
-		to compile. Valid values are rva20u64 (default), rva22u64.
+		to compile. Valid values are rva20u64 (default), rva22u64, rva23u64.
 		See https://github.com/riscv/riscv-profiles/blob/main/src/profiles.adoc
+		and https://github.com/riscv/riscv-profiles/blob/main/src/rva23-profile.adoc
 	GOWASM
 		For GOARCH=wasm, comma-separated list of experimental WebAssembly features to use.
 		Valid values are satconv, signext.
@@ -951,8 +952,8 @@ The defined architecture feature build tags are:
 	  (or ppc64le.power8, ppc64le.power9, and ppc64le.power10)
 	  feature build tags.
 	- For GOARCH=riscv64,
-	  GORISCV64=rva20u64 and rva22u64 correspond to the riscv64.rva20u64
-	  and riscv64.rva22u64 build tags.
+	  GORISCV64=rva20u64, rva22u64 and rva23u64 correspond to the riscv64.rva20u64,
+	  riscv64.rva22u64 and riscv64.rva23u64 build tags.
 	- For GOARCH=wasm, GOWASM=satconv and signext
 	  correspond to the wasm.satconv and wasm.signext feature build tags.
 

src/cmd/go/testdata/script/tooltags.txt

@@ -50,10 +50,15 @@ env GORISCV64=rva22u64
 go list -f '{{context.ToolTags}}'
 stdout 'riscv64.rva20u64 riscv64.rva22u64'
 
+env GOARCH=riscv64
+env GORISCV64=rva23u64
+go list -f '{{context.ToolTags}}'
+stdout 'riscv64.rva20u64 riscv64.rva22u64 riscv64.rva23u64'
+
 env GOARCH=riscv64
 env GORISCV64=rva22
 ! go list -f '{{context.ToolTags}}'
-stderr 'go: invalid GORISCV64: must be rva20u64, rva22u64'
+stderr 'go: invalid GORISCV64: must be rva20u64, rva22u64, rva23u64'
 
 env GOARCH=riscv64
 env GORISCV64=

src/cmd/internal/testdir/testdir_test.go

@@ -1489,7 +1489,7 @@ var (
 		"ppc64x":  {}, // A pseudo-arch representing both ppc64 and ppc64le
 		"s390x":   {},
 		"wasm":    {},
-		"riscv64": {"GORISCV64", "rva20u64", "rva22u64"},
+		"riscv64": {"GORISCV64", "rva20u64", "rva22u64", "rva23u64"},
 	}
 )
 

src/internal/buildcfg/cfg.go

@@ -307,8 +307,10 @@ func goriscv64() int {
 		return 20
 	case "rva22u64":
 		return 22
+	case "rva23u64":
+		return 23
 	}
-	Error = fmt.Errorf("invalid GORISCV64: must be rva20u64, rva22u64")
+	Error = fmt.Errorf("invalid GORISCV64: must be rva20u64, rva22u64, rva23u64")
 	v := DefaultGORISCV64[len("rva"):]
 	i := strings.IndexFunc(v, func(r rune) bool {
 		return r < '0' || r > '9'
@@ -441,6 +443,9 @@ func gogoarchTags() []string {
 		if GORISCV64 >= 22 {
 			list = append(list, GOARCH+"."+"rva22u64")
 		}
+		if GORISCV64 >= 23 {
+			list = append(list, GOARCH+"."+"rva23u64")
+		}
 		return list
 	case "wasm":
 		var list []string

src/internal/buildcfg/cfg_test.go

@@ -32,6 +32,10 @@ func TestConfigFlags(t *testing.T) {
 	if goriscv64() != 22 {
 		t.Errorf("Wrong parsing of RISCV64=rva22u64")
 	}
+	os.Setenv("GORISCV64", "rva23u64")
+	if goriscv64() != 23 {
+		t.Errorf("Wrong parsing of RISCV64=rva23u64")
+	}
 	Error = nil
 	os.Setenv("GORISCV64", "rva22")
 	if _ = goriscv64(); Error == nil {

src/runtime/asm_riscv64.h

@@ -10,3 +10,12 @@
 #define hasZbb
 #define hasZbs
 #endif
+
+#ifdef GORISCV64_rva23u64
+#define hasV
+#define hasZba
+#define hasZbb
+#define hasZbs
+#define hasZfa
+#define hasZicond
+#endif