cmd/compile,runtime: remove runtime.mulUintptr

For #48798

Change-Id: I3e928d3921cfd5a7bf35b23d0ae6442aa6d2d482
GitHub-Last-Rev: b101a8a54f2cc9ea917f879a545f30c702508743
GitHub-Pull-Request: golang/go#63349
Reviewed-on: https://go-review.googlesource.com/c/go/+/532355
TryBot-Result: Gopher Robot <[email protected]>
Commit-Queue: Keith Randall <[email protected]>
Reviewed-by: Keith Randall <[email protected]>
Run-TryBot: Martin Möhrmann <[email protected]>
Reviewed-by: Keith Randall <[email protected]>
Auto-Submit: Keith Randall <[email protected]>
Reviewed-by: Martin Möhrmann <[email protected]>

src/cmd/compile/internal/ssagen/ssa.go

@@ -4117,7 +4117,6 @@ func InitTables() {
  return s.newValue2(ssa.OpMul64uover, types.NewTuple(types.Types[types.TUINT], types.Types[types.TUINT]), args[0], args[1])
  },
  sys.AMD64, sys.I386, sys.Loong64, sys.MIPS64, sys.RISCV64, sys.ARM64)
- alias("runtime", "mulUintptr", "runtime/internal/math", "MulUintptr", all...)
  add("runtime", "KeepAlive",
  func(s *state, n *ir.CallExpr, args []*ssa.Value) *ssa.Value {
  data := s.newValue1(ssa.OpIData, s.f.Config.Types.BytePtr, args[0])

src/cmd/compile/internal/typecheck/_builtin/runtime.go

@@ -189,8 +189,6 @@ func unsafestringcheckptr(ptr unsafe.Pointer, len int64)
 func panicunsafestringlen()
 func panicunsafestringnilptr()
 
-func mulUintptr(x, y uintptr) (uintptr, bool)
-
 func memmove(to *any, frm *any, length uintptr)
 func memclrNoHeapPointers(ptr unsafe.Pointer, n uintptr)
 func memclrHasPointers(ptr unsafe.Pointer, n uintptr)

src/cmd/compile/internal/walk/builtin.go

@@ -748,11 +748,23 @@ func walkUnsafeSlice(n *ir.BinaryExpr, init *ir.Nodes) ir.Node {
  return walkExpr(typecheck.Expr(h), init)
  }
 
- // mem, overflow := runtime.mulUintptr(et.size, len)
+ // mem, overflow := math.mulUintptr(et.size, len)
  mem := typecheck.TempAt(base.Pos, ir.CurFunc, types.Types[types.TUINTPTR])
  overflow := typecheck.TempAt(base.Pos, ir.CurFunc, types.Types[types.TBOOL])
- fn := typecheck.LookupRuntime("mulUintptr")
- call := mkcall1(fn, fn.Type().ResultsTuple(), init, ir.NewInt(base.Pos, sliceType.Elem().Size()), typecheck.Conv(typecheck.Conv(len, lenType), types.Types[types.TUINTPTR]))
+
+ decl := types.NewSignature(nil,
+ []*types.Field{
+ types.NewField(base.Pos, nil, types.Types[types.TUINTPTR]),
+ types.NewField(base.Pos, nil, types.Types[types.TUINTPTR]),
+ },
+ []*types.Field{
+ types.NewField(base.Pos, nil, types.Types[types.TUINTPTR]),
+ types.NewField(base.Pos, nil, types.Types[types.TBOOL]),
+ })
+
+ fn := ir.NewFunc(n.Pos(), n.Pos(), math_MulUintptr, decl)
+
+ call := mkcall1(fn.Nname, fn.Type().ResultsTuple(), init, ir.NewInt(base.Pos, sliceType.Elem().Size()), typecheck.Conv(typecheck.Conv(len, lenType), types.Types[types.TUINTPTR]))
  appendWalkStmt(init, ir.NewAssignListStmt(base.Pos, ir.OAS2, []ir.Node{mem, overflow}, []ir.Node{call}))
 
  // if overflow || mem > -uintptr(ptr) {
@@ -778,6 +790,8 @@ func walkUnsafeSlice(n *ir.BinaryExpr, init *ir.Nodes) ir.Node {
  return walkExpr(typecheck.Expr(h), init)
 }
 
+var math_MulUintptr = &types.Sym{Pkg: types.NewPkg("runtime/internal/math", "math"), Name: "MulUintptr"}
+
 func walkUnsafeString(n *ir.BinaryExpr, init *ir.Nodes) ir.Node {
  ptr := safeExpr(n.X, init)
  len := safeExpr(n.Y, init)

src/runtime/slice.go

@@ -117,12 +117,6 @@ func makeslice64(et *_type, len64, cap64 int64) unsafe.Pointer {
  return makeslice(et, len, cap)
 }
 
-// This is a wrapper over runtime/internal/math.MulUintptr,
-// so the compiler can recognize and treat it as an intrinsic.
-func mulUintptr(a, b uintptr) (uintptr, bool) {
- return math.MulUintptr(a, b)
-}
-
 // growslice allocates new backing store for a slice.
 //
 // arguments: