cmd/compile/internal/gc: add support for GOARCH=mips{,le}

Change-Id: Ida4cd647525abce3441bfcb9fdee059344fe717f
Reviewed-on: https://go-review.googlesource.com/31477
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Cherry Zhang <cherryyz@google.com>

3 files changed, 164 insertions, 43 deletions

diff --git a/src/cmd/compile/internal/gc/pgen.go b/src/cmd/compile/internal/gc/pgen.go
index 5ae493bc82..91256229a7 100644
--- a/src/cmd/compile/internal/gc/pgen.go
+++ b/src/cmd/compile/internal/gc/pgen.go
@@ -279,7 +279,7 @@ func (s *ssaExport) AllocFrame(f *ssa.Func) {
 		if haspointers(n.Type) {
 			stkptrsize = Stksize
 		}
-		if Thearch.LinkArch.InFamily(sys.MIPS64, sys.ARM, sys.ARM64, sys.PPC64, sys.S390X) {
+		if Thearch.LinkArch.InFamily(sys.MIPS, sys.MIPS64, sys.ARM, sys.ARM64, sys.PPC64, sys.S390X) {
 			Stksize = Rnd(Stksize, int64(Widthptr))
 		}
 		if Stksize >= 1<<31 {
diff --git a/src/cmd/compile/internal/gc/ssa.go b/src/cmd/compile/internal/gc/ssa.go
index 76becdc795..55ee3c01dc 100644
--- a/src/cmd/compile/internal/gc/ssa.go
+++ b/src/cmd/compile/internal/gc/ssa.go
@@ -6,6 +6,7 @@ package gc
 
 import (
 	"bytes"
+	"encoding/binary"
 	"fmt"
 	"html"
 	"os"
@@ -1659,7 +1660,7 @@ func (s *state) expr(n *Node) *ssa.Value {
 
 		if ft.IsFloat() || tt.IsFloat() {
 			conv, ok := fpConvOpToSSA[twoTypes{s.concreteEtype(ft), s.concreteEtype(tt)}]
-			if s.config.IntSize == 4 && Thearch.LinkArch.Name != "amd64p32" {
+			if s.config.IntSize == 4 && Thearch.LinkArch.Name != "amd64p32" && Thearch.LinkArch.Family != sys.MIPS {
 				if conv1, ok1 := fpConvOpToSSA32[twoTypes{s.concreteEtype(ft), s.concreteEtype(tt)}]; ok1 {
 					conv = conv1
 				}
@@ -1669,6 +1670,27 @@ func (s *state) expr(n *Node) *ssa.Value {
 					conv = conv1
 				}
 			}
+
+			if Thearch.LinkArch.Family == sys.MIPS {
+				if ft.Size() == 4 && ft.IsInteger() && !ft.IsSigned() {
+					// tt is float32 or float64, and ft is also unsigned
+					if tt.Size() == 4 {
+						return s.uint32Tofloat32(n, x, ft, tt)
+					}
+					if tt.Size() == 8 {
+						return s.uint32Tofloat64(n, x, ft, tt)
+					}
+				} else if tt.Size() == 4 && tt.IsInteger() && !tt.IsSigned() {
+					// ft is float32 or float64, and tt is unsigned integer
+					if ft.Size() == 4 {
+						return s.float32ToUint32(n, x, ft, tt)
+					}
+					if ft.Size() == 8 {
+						return s.float64ToUint32(n, x, ft, tt)
+					}
+				}
+			}
+
 			if !ok {
 				s.Fatalf("weird float conversion %v -> %v", ft, tt)
 			}
@@ -1689,7 +1711,7 @@ func (s *state) expr(n *Node) *ssa.Value {
 			}
 			// Tricky 64-bit unsigned cases.
 			if ft.IsInteger() {
-				// therefore tt is float32 or float64, and ft is also unsigned
+				// tt is float32 or float64, and ft is also unsigned
 				if tt.Size() == 4 {
 					return s.uint64Tofloat32(n, x, ft, tt)
 				}
@@ -1698,7 +1720,7 @@ func (s *state) expr(n *Node) *ssa.Value {
 				}
 				s.Fatalf("weird unsigned integer to float conversion %v -> %v", ft, tt)
 			}
-			// therefore ft is float32 or float64, and tt is unsigned integer
+			// ft is float32 or float64, and tt is unsigned integer
 			if ft.Size() == 4 {
 				return s.float32ToUint64(n, x, ft, tt)
 			}
@@ -2588,10 +2610,10 @@ func intrinsicInit() {
 		/******** runtime/internal/sys ********/
 		intrinsicKey{"runtime/internal/sys", "Ctz32"}: enableOnArch(func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
 			return s.newValue1(ssa.OpCtz32, Types[TUINT32], args[0])
-		}, sys.AMD64, sys.ARM64, sys.ARM, sys.S390X),
+		}, sys.AMD64, sys.ARM64, sys.ARM, sys.S390X, sys.MIPS),
 		intrinsicKey{"runtime/internal/sys", "Ctz64"}: enableOnArch(func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
 			return s.newValue1(ssa.OpCtz64, Types[TUINT64], args[0])
-		}, sys.AMD64, sys.ARM64, sys.ARM, sys.S390X),
+		}, sys.AMD64, sys.ARM64, sys.ARM, sys.S390X, sys.MIPS),
 		intrinsicKey{"runtime/internal/sys", "Bswap32"}: enableOnArch(func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
 			return s.newValue1(ssa.OpBswap32, Types[TUINT32], args[0])
 		}, sys.AMD64, sys.ARM64, sys.ARM, sys.S390X),
@@ -2604,7 +2626,7 @@ func intrinsicInit() {
 			v := s.newValue2(ssa.OpAtomicLoad32, ssa.MakeTuple(Types[TUINT32], ssa.TypeMem), args[0], s.mem())
 			s.vars[&memVar] = s.newValue1(ssa.OpSelect1, ssa.TypeMem, v)
 			return s.newValue1(ssa.OpSelect0, Types[TUINT32], v)
-		}, sys.AMD64, sys.ARM64, sys.S390X),
+		}, sys.AMD64, sys.ARM64, sys.S390X, sys.MIPS),
 		intrinsicKey{"runtime/internal/atomic", "Load64"}: enableOnArch(func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
 			v := s.newValue2(ssa.OpAtomicLoad64, ssa.MakeTuple(Types[TUINT64], ssa.TypeMem), args[0], s.mem())
 			s.vars[&memVar] = s.newValue1(ssa.OpSelect1, ssa.TypeMem, v)
@@ -2614,12 +2636,12 @@ func intrinsicInit() {
 			v := s.newValue2(ssa.OpAtomicLoadPtr, ssa.MakeTuple(ptrto(Types[TUINT8]), ssa.TypeMem), args[0], s.mem())
 			s.vars[&memVar] = s.newValue1(ssa.OpSelect1, ssa.TypeMem, v)
 			return s.newValue1(ssa.OpSelect0, ptrto(Types[TUINT8]), v)
-		}, sys.AMD64, sys.ARM64, sys.S390X),
+		}, sys.AMD64, sys.ARM64, sys.S390X, sys.MIPS),
 
 		intrinsicKey{"runtime/internal/atomic", "Store"}: enableOnArch(func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
 			s.vars[&memVar] = s.newValue3(ssa.OpAtomicStore32, ssa.TypeMem, args[0], args[1], s.mem())
 			return nil
-		}, sys.AMD64, sys.ARM64, sys.S390X),
+		}, sys.AMD64, sys.ARM64, sys.S390X, sys.MIPS),
 		intrinsicKey{"runtime/internal/atomic", "Store64"}: enableOnArch(func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
 			s.vars[&memVar] = s.newValue3(ssa.OpAtomicStore64, ssa.TypeMem, args[0], args[1], s.mem())
 			return nil
@@ -2627,13 +2649,13 @@ func intrinsicInit() {
 		intrinsicKey{"runtime/internal/atomic", "StorepNoWB"}: enableOnArch(func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
 			s.vars[&memVar] = s.newValue3(ssa.OpAtomicStorePtrNoWB, ssa.TypeMem, args[0], args[1], s.mem())
 			return nil
-		}, sys.AMD64, sys.ARM64, sys.S390X),
+		}, sys.AMD64, sys.ARM64, sys.S390X, sys.MIPS),
 
 		intrinsicKey{"runtime/internal/atomic", "Xchg"}: enableOnArch(func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
 			v := s.newValue3(ssa.OpAtomicExchange32, ssa.MakeTuple(Types[TUINT32], ssa.TypeMem), args[0], args[1], s.mem())
 			s.vars[&memVar] = s.newValue1(ssa.OpSelect1, ssa.TypeMem, v)
 			return s.newValue1(ssa.OpSelect0, Types[TUINT32], v)
-		}, sys.AMD64, sys.ARM64, sys.S390X),
+		}, sys.AMD64, sys.ARM64, sys.S390X, sys.MIPS),
 		intrinsicKey{"runtime/internal/atomic", "Xchg64"}: enableOnArch(func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
 			v := s.newValue3(ssa.OpAtomicExchange64, ssa.MakeTuple(Types[TUINT64], ssa.TypeMem), args[0], args[1], s.mem())
 			s.vars[&memVar] = s.newValue1(ssa.OpSelect1, ssa.TypeMem, v)
@@ -2644,7 +2666,7 @@ func intrinsicInit() {
 			v := s.newValue3(ssa.OpAtomicAdd32, ssa.MakeTuple(Types[TUINT32], ssa.TypeMem), args[0], args[1], s.mem())
 			s.vars[&memVar] = s.newValue1(ssa.OpSelect1, ssa.TypeMem, v)
 			return s.newValue1(ssa.OpSelect0, Types[TUINT32], v)
-		}, sys.AMD64, sys.ARM64, sys.S390X),
+		}, sys.AMD64, sys.ARM64, sys.S390X, sys.MIPS),
 		intrinsicKey{"runtime/internal/atomic", "Xadd64"}: enableOnArch(func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
 			v := s.newValue3(ssa.OpAtomicAdd64, ssa.MakeTuple(Types[TUINT64], ssa.TypeMem), args[0], args[1], s.mem())
 			s.vars[&memVar] = s.newValue1(ssa.OpSelect1, ssa.TypeMem, v)
@@ -2655,7 +2677,7 @@ func intrinsicInit() {
 			v := s.newValue4(ssa.OpAtomicCompareAndSwap32, ssa.MakeTuple(Types[TBOOL], ssa.TypeMem), args[0], args[1], args[2], s.mem())
 			s.vars[&memVar] = s.newValue1(ssa.OpSelect1, ssa.TypeMem, v)
 			return s.newValue1(ssa.OpSelect0, Types[TBOOL], v)
-		}, sys.AMD64, sys.ARM64, sys.S390X),
+		}, sys.AMD64, sys.ARM64, sys.S390X, sys.MIPS),
 		intrinsicKey{"runtime/internal/atomic", "Cas64"}: enableOnArch(func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
 			v := s.newValue4(ssa.OpAtomicCompareAndSwap64, ssa.MakeTuple(Types[TBOOL], ssa.TypeMem), args[0], args[1], args[2], s.mem())
 			s.vars[&memVar] = s.newValue1(ssa.OpSelect1, ssa.TypeMem, v)
@@ -2665,11 +2687,11 @@ func intrinsicInit() {
 		intrinsicKey{"runtime/internal/atomic", "And8"}: enableOnArch(func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
 			s.vars[&memVar] = s.newValue3(ssa.OpAtomicAnd8, ssa.TypeMem, args[0], args[1], s.mem())
 			return nil
-		}, sys.AMD64, sys.ARM64),
+		}, sys.AMD64, sys.ARM64, sys.MIPS),
 		intrinsicKey{"runtime/internal/atomic", "Or8"}: enableOnArch(func(s *state, n *Node, args []*ssa.Value) *ssa.Value {
 			s.vars[&memVar] = s.newValue3(ssa.OpAtomicOr8, ssa.TypeMem, args[0], args[1], s.mem())
 			return nil
-		}, sys.AMD64, sys.ARM64),
+		}, sys.AMD64, sys.ARM64, sys.MIPS),
 	}
 
 	// aliases internal to runtime/internal/atomic
@@ -3676,12 +3698,12 @@ func (s *state) slice(t *Type, v, i, j, k *ssa.Value) (p, l, c *ssa.Value) {
 	return rptr, rlen, rcap
 }
 
-type u2fcvtTab struct {
+type u642fcvtTab struct {
 	geq, cvt2F, and, rsh, or, add ssa.Op
 	one                           func(*state, ssa.Type, int64) *ssa.Value
 }
 
-var u64_f64 u2fcvtTab = u2fcvtTab{
+var u64_f64 u642fcvtTab = u642fcvtTab{
 	geq:   ssa.OpGeq64,
 	cvt2F: ssa.OpCvt64to64F,
 	and:   ssa.OpAnd64,
@@ -3691,7 +3713,7 @@ var u64_f64 u2fcvtTab = u2fcvtTab{
 	one:   (*state).constInt64,
 }
 
-var u64_f32 u2fcvtTab = u2fcvtTab{
+var u64_f32 u642fcvtTab = u642fcvtTab{
 	geq:   ssa.OpGeq64,
 	cvt2F: ssa.OpCvt64to32F,
 	and:   ssa.OpAnd64,
@@ -3702,14 +3724,14 @@ var u64_f32 u2fcvtTab = u2fcvtTab{
 }
 
 func (s *state) uint64Tofloat64(n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
-	return s.uintTofloat(&u64_f64, n, x, ft, tt)
+	return s.uint64Tofloat(&u64_f64, n, x, ft, tt)
 }
 
 func (s *state) uint64Tofloat32(n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
-	return s.uintTofloat(&u64_f32, n, x, ft, tt)
+	return s.uint64Tofloat(&u64_f32, n, x, ft, tt)
 }
 
-func (s *state) uintTofloat(cvttab *u2fcvtTab, n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
+func (s *state) uint64Tofloat(cvttab *u642fcvtTab, n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
 	// if x >= 0 {
 	//    result = (floatY) x
 	// } else {
@@ -3768,6 +3790,66 @@ func (s *state) uintTofloat(cvttab *u2fcvtTab, n *Node, x *ssa.Value, ft, tt *Ty
 	return s.variable(n, n.Type)
 }
 
+type u322fcvtTab struct {
+	cvtI2F, cvtF2F ssa.Op
+}
+
+var u32_f64 u322fcvtTab = u322fcvtTab{
+	cvtI2F: ssa.OpCvt32to64F,
+	cvtF2F: ssa.OpCopy,
+}
+
+var u32_f32 u322fcvtTab = u322fcvtTab{
+	cvtI2F: ssa.OpCvt32to32F,
+	cvtF2F: ssa.OpCvt64Fto32F,
+}
+
+func (s *state) uint32Tofloat64(n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
+	return s.uint32Tofloat(&u32_f64, n, x, ft, tt)
+}
+
+func (s *state) uint32Tofloat32(n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
+	return s.uint32Tofloat(&u32_f32, n, x, ft, tt)
+}
+
+func (s *state) uint32Tofloat(cvttab *u322fcvtTab, n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
+	// if x >= 0 {
+	// 	result = floatY(x)
+	// } else {
+	// 	result = floatY(float64(x) + (1<<32))
+	// }
+	cmp := s.newValue2(ssa.OpGeq32, Types[TBOOL], x, s.zeroVal(ft))
+	b := s.endBlock()
+	b.Kind = ssa.BlockIf
+	b.SetControl(cmp)
+	b.Likely = ssa.BranchLikely
+
+	bThen := s.f.NewBlock(ssa.BlockPlain)
+	bElse := s.f.NewBlock(ssa.BlockPlain)
+	bAfter := s.f.NewBlock(ssa.BlockPlain)
+
+	b.AddEdgeTo(bThen)
+	s.startBlock(bThen)
+	a0 := s.newValue1(cvttab.cvtI2F, tt, x)
+	s.vars[n] = a0
+	s.endBlock()
+	bThen.AddEdgeTo(bAfter)
+
+	b.AddEdgeTo(bElse)
+	s.startBlock(bElse)
+	a1 := s.newValue1(ssa.OpCvt32to64F, Types[TFLOAT64], x)
+	twoToThe32 := s.constFloat64(Types[TFLOAT64], float64(1<<32))
+	a2 := s.newValue2(ssa.OpAdd64F, Types[TFLOAT64], a1, twoToThe32)
+	a3 := s.newValue1(cvttab.cvtF2F, tt, a2)
+
+	s.vars[n] = a3
+	s.endBlock()
+	bElse.AddEdgeTo(bAfter)
+
+	s.startBlock(bAfter)
+	return s.variable(n, n.Type)
+}
+
 // referenceTypeBuiltin generates code for the len/cap builtins for maps and channels.
 func (s *state) referenceTypeBuiltin(n *Node, x *ssa.Value) *ssa.Value {
 	if !n.Left.Type.IsMap() && !n.Left.Type.IsChan() {
@@ -3820,22 +3902,50 @@ func (s *state) referenceTypeBuiltin(n *Node, x *ssa.Value) *ssa.Value {
 }
 
 type f2uCvtTab struct {
-	ltf, cvt2U, subf ssa.Op
-	value            func(*state, ssa.Type, float64) *ssa.Value
+	ltf, cvt2U, subf, or ssa.Op
+	floatValue           func(*state, ssa.Type, float64) *ssa.Value
+	intValue             func(*state, ssa.Type, int64) *ssa.Value
+	cutoff               uint64
 }
 
 var f32_u64 f2uCvtTab = f2uCvtTab{
-	ltf:   ssa.OpLess32F,
-	cvt2U: ssa.OpCvt32Fto64,
-	subf:  ssa.OpSub32F,
-	value: (*state).constFloat32,
+	ltf:        ssa.OpLess32F,
+	cvt2U:      ssa.OpCvt32Fto64,
+	subf:       ssa.OpSub32F,
+	or:         ssa.OpOr64,
+	floatValue: (*state).constFloat32,
+	intValue:   (*state).constInt64,
+	cutoff:     9223372036854775808,
 }
 
 var f64_u64 f2uCvtTab = f2uCvtTab{
-	ltf:   ssa.OpLess64F,
-	cvt2U: ssa.OpCvt64Fto64,
-	subf:  ssa.OpSub64F,
-	value: (*state).constFloat64,
+	ltf:        ssa.OpLess64F,
+	cvt2U:      ssa.OpCvt64Fto64,
+	subf:       ssa.OpSub64F,
+	or:         ssa.OpOr64,
+	floatValue: (*state).constFloat64,
+	intValue:   (*state).constInt64,
+	cutoff:     9223372036854775808,
+}
+
+var f32_u32 f2uCvtTab = f2uCvtTab{
+	ltf:        ssa.OpLess32F,
+	cvt2U:      ssa.OpCvt32Fto32,
+	subf:       ssa.OpSub32F,
+	or:         ssa.OpOr32,
+	floatValue: (*state).constFloat32,
+	intValue:   func(s *state, t ssa.Type, v int64) *ssa.Value { return s.constInt32(t, int32(v)) },
+	cutoff:     2147483648,
+}
+
+var f64_u32 f2uCvtTab = f2uCvtTab{
+	ltf:        ssa.OpLess64F,
+	cvt2U:      ssa.OpCvt64Fto32,
+	subf:       ssa.OpSub64F,
+	or:         ssa.OpOr32,
+	floatValue: (*state).constFloat64,
+	intValue:   func(s *state, t ssa.Type, v int64) *ssa.Value { return s.constInt32(t, int32(v)) },
+	cutoff:     2147483648,
 }
 
 func (s *state) float32ToUint64(n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
@@ -3845,16 +3955,25 @@ func (s *state) float64ToUint64(n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value
 	return s.floatToUint(&f64_u64, n, x, ft, tt)
 }
 
+func (s *state) float32ToUint32(n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
+	return s.floatToUint(&f32_u32, n, x, ft, tt)
+}
+
+func (s *state) float64ToUint32(n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
+	return s.floatToUint(&f64_u32, n, x, ft, tt)
+}
+
 func (s *state) floatToUint(cvttab *f2uCvtTab, n *Node, x *ssa.Value, ft, tt *Type) *ssa.Value {
-	// if x < 9223372036854775808.0 {
+	// cutoff:=1<<(intY_Size-1)
+	// if x < floatX(cutoff) {
 	// 	result = uintY(x)
 	// } else {
-	// 	y = x - 9223372036854775808.0
+	// 	y = x - floatX(cutoff)
 	// 	z = uintY(y)
-	// 	result = z | -9223372036854775808
+	// 	result = z | -(cutoff)
 	// }
-	twoToThe63 := cvttab.value(s, ft, 9223372036854775808.0)
-	cmp := s.newValue2(cvttab.ltf, Types[TBOOL], x, twoToThe63)
+	cutoff := cvttab.floatValue(s, ft, float64(cvttab.cutoff))
+	cmp := s.newValue2(cvttab.ltf, Types[TBOOL], x, cutoff)
 	b := s.endBlock()
 	b.Kind = ssa.BlockIf
 	b.SetControl(cmp)
@@ -3873,10 +3992,10 @@ func (s *state) floatToUint(cvttab *f2uCvtTab, n *Node, x *ssa.Value, ft, tt *Ty
 
 	b.AddEdgeTo(bElse)
 	s.startBlock(bElse)
-	y := s.newValue2(cvttab.subf, ft, x, twoToThe63)
+	y := s.newValue2(cvttab.subf, ft, x, cutoff)
 	y = s.newValue1(cvttab.cvt2U, tt, y)
-	z := s.constInt64(tt, -9223372036854775808)
-	a1 := s.newValue2(ssa.OpOr64, tt, y, z)
+	z := cvttab.intValue(s, tt, int64(-cvttab.cutoff))
+	a1 := s.newValue2(cvttab.or, tt, y, z)
 	s.vars[n] = a1
 	s.endBlock()
 	bElse.AddEdgeTo(bAfter)
@@ -4776,7 +4895,9 @@ func (e *ssaExport) SplitInt64(name ssa.LocalSlot) (ssa.LocalSlot, ssa.LocalSlot
 		return ssa.LocalSlot{N: h, Type: t, Off: 0}, ssa.LocalSlot{N: l, Type: Types[TUINT32], Off: 0}
 	}
 	// Return the two parts of the larger variable.
-	// Assuming little endian (we don't support big endian 32-bit architecture yet)
+	if Thearch.LinkArch.ByteOrder == binary.BigEndian {
+		return ssa.LocalSlot{N: n, Type: t, Off: name.Off}, ssa.LocalSlot{N: n, Type: Types[TUINT32], Off: name.Off + 4}
+	}
 	return ssa.LocalSlot{N: n, Type: t, Off: name.Off + 4}, ssa.LocalSlot{N: n, Type: Types[TUINT32], Off: name.Off}
 }
 
diff --git a/src/cmd/compile/internal/gc/walk.go b/src/cmd/compile/internal/gc/walk.go
index c1caa47480..3adfd465d8 100644
--- a/src/cmd/compile/internal/gc/walk.go
+++ b/src/cmd/compile/internal/gc/walk.go
@@ -686,7 +686,7 @@ opswitch:
 
 		if n.Left.Op == ONAME && n.Left.Sym.Name == "Sqrt" &&
 			(n.Left.Sym.Pkg.Path == "math" || n.Left.Sym.Pkg == localpkg && myimportpath == "math") {
-			if Thearch.LinkArch.InFamily(sys.AMD64, sys.ARM, sys.ARM64, sys.PPC64, sys.S390X) {
+			if Thearch.LinkArch.InFamily(sys.AMD64, sys.ARM, sys.ARM64, sys.MIPS, sys.PPC64, sys.S390X) {
 				n.Op = OSQRT
 				n.Left = n.List.First()
 				n.List.Set(nil)
@@ -1018,7 +1018,7 @@ opswitch:
 		n = walkexpr(n, init)
 
 	case OCONV, OCONVNOP:
-		if Thearch.LinkArch.Family == sys.ARM {
+		if Thearch.LinkArch.Family == sys.ARM || Thearch.LinkArch.Family == sys.MIPS {
 			if n.Left.Type.IsFloat() {
 				if n.Type.Etype == TINT64 {
 					n = mkcall("float64toint64", n.Type, init, conv(n.Left, Types[TFLOAT64]))
@@ -3277,7 +3277,7 @@ func samecheap(a *Node, b *Node) bool {
 // The result of walkrotate MUST be assigned back to n, e.g.
 // 	n.Left = walkrotate(n.Left)
 func walkrotate(n *Node) *Node {
-	if Thearch.LinkArch.InFamily(sys.MIPS64, sys.PPC64) {
+	if Thearch.LinkArch.InFamily(sys.MIPS, sys.MIPS64, sys.PPC64) {
 		return n
 	}