cmd/compile: use slices.SortStableFunc

Now that we're bootstrapping from a toolchain that has the slices
package.

Updates #64751

Change-Id: I876ec6d261466344faf33f8c5cda229dd1e4185f
Reviewed-on: https://go-review.googlesource.com/c/go/+/610602
Auto-Submit: Cuong Manh Le <[email protected]>
Reviewed-by: Dmitri Shuralyov <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>
Reviewed-by: Cherry Mui <[email protected]>

Author: cuonglm

src/cmd/compile/internal/inline/inlheur/analyze.go

@@ -8,13 +8,14 @@ import (
 	"cmd/compile/internal/base"
 	"cmd/compile/internal/ir"
 	"cmd/compile/internal/types"
+	"cmp"
 	"encoding/json"
 	"fmt"
 	"internal/buildcfg"
 	"io"
 	"os"
 	"path/filepath"
-	"sort"
+	"slices"
 	"strings"
 )
 
@@ -349,11 +350,11 @@ func dumpFnPreamble(w io.Writer, funcInlHeur *fnInlHeur, ecst encodedCallSiteTab
 // sortFnInlHeurSlice sorts a slice of fnInlHeur based on
 // the starting line of the function definition, then by name.
 func sortFnInlHeurSlice(sl []fnInlHeur) []fnInlHeur {
-	sort.SliceStable(sl, func(i, j int) bool {
-		if sl[i].line != sl[j].line {
-			return sl[i].line < sl[j].line
+	slices.SortStableFunc(sl, func(a, b fnInlHeur) int {
+		if a.line != b.line {
+			return cmp.Compare(a.line, b.line)
 		}
-		return sl[i].fname < sl[j].fname
+		return strings.Compare(a.fname, b.fname)
 	})
 	return sl
 }

src/cmd/compile/internal/liveness/mergelocals.go

@@ -161,8 +161,8 @@ func (mls *MergeLocalsState) Followers(n *ir.Name, tmp []*ir.Name) []*ir.Name {
 	for _, k := range sl[1:] {
 		tmp = append(tmp, mls.vars[k])
 	}
-	sort.SliceStable(tmp, func(i, j int) bool {
-		return tmp[i].Sym().Name < tmp[j].Sym().Name
+	slices.SortStableFunc(tmp, func(a, b *ir.Name) int {
+		return strings.Compare(a.Sym().Name, b.Sym().Name)
 	})
 	return tmp
 }