cmd/compile: constant fold modulo
Fixes #15079
Change-Id: Ib4dd9eab322da39234008e040100e75cb58761b3
Reviewed-on: https://go-review.googlesource.com/21501
Reviewed-by: David Chase <drchase@google.com>
Run-TryBot: Alexandru Moșoi <alexandru@mosoi.ro>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/src/cmd/compile/internal/ssa/rewritegeneric.go b/src/cmd/compile/internal/ssa/rewritegeneric.go
index 14b1769..932cb42 100644
--- a/src/cmd/compile/internal/ssa/rewritegeneric.go
+++ b/src/cmd/compile/internal/ssa/rewritegeneric.go
@@ -174,10 +174,22 @@
return rewriteValuegeneric_OpLsh8x64(v, config)
case OpLsh8x8:
return rewriteValuegeneric_OpLsh8x8(v, config)
+ case OpMod16:
+ return rewriteValuegeneric_OpMod16(v, config)
+ case OpMod16u:
+ return rewriteValuegeneric_OpMod16u(v, config)
+ case OpMod32:
+ return rewriteValuegeneric_OpMod32(v, config)
+ case OpMod32u:
+ return rewriteValuegeneric_OpMod32u(v, config)
case OpMod64:
return rewriteValuegeneric_OpMod64(v, config)
case OpMod64u:
return rewriteValuegeneric_OpMod64u(v, config)
+ case OpMod8:
+ return rewriteValuegeneric_OpMod8(v, config)
+ case OpMod8u:
+ return rewriteValuegeneric_OpMod8u(v, config)
case OpMul16:
return rewriteValuegeneric_OpMul16(v, config)
case OpMul32:
@@ -4409,11 +4421,136 @@
}
return false
}
+func rewriteValuegeneric_OpMod16(v *Value, config *Config) bool {
+ b := v.Block
+ _ = b
+ // match: (Mod16 (Const16 [c]) (Const16 [d]))
+ // cond: d != 0
+ // result: (Const16 [int64(int16(c % d))])
+ for {
+ v_0 := v.Args[0]
+ if v_0.Op != OpConst16 {
+ break
+ }
+ c := v_0.AuxInt
+ v_1 := v.Args[1]
+ if v_1.Op != OpConst16 {
+ break
+ }
+ d := v_1.AuxInt
+ if !(d != 0) {
+ break
+ }
+ v.reset(OpConst16)
+ v.AuxInt = int64(int16(c % d))
+ return true
+ }
+ return false
+}
+func rewriteValuegeneric_OpMod16u(v *Value, config *Config) bool {
+ b := v.Block
+ _ = b
+ // match: (Mod16u (Const16 [c]) (Const16 [d]))
+ // cond: d != 0
+ // result: (Const16 [int64(uint16(c) % uint16(d))])
+ for {
+ v_0 := v.Args[0]
+ if v_0.Op != OpConst16 {
+ break
+ }
+ c := v_0.AuxInt
+ v_1 := v.Args[1]
+ if v_1.Op != OpConst16 {
+ break
+ }
+ d := v_1.AuxInt
+ if !(d != 0) {
+ break
+ }
+ v.reset(OpConst16)
+ v.AuxInt = int64(uint16(c) % uint16(d))
+ return true
+ }
+ return false
+}
+func rewriteValuegeneric_OpMod32(v *Value, config *Config) bool {
+ b := v.Block
+ _ = b
+ // match: (Mod32 (Const32 [c]) (Const32 [d]))
+ // cond: d != 0
+ // result: (Const32 [int64(int32(c % d))])
+ for {
+ v_0 := v.Args[0]
+ if v_0.Op != OpConst32 {
+ break
+ }
+ c := v_0.AuxInt
+ v_1 := v.Args[1]
+ if v_1.Op != OpConst32 {
+ break
+ }
+ d := v_1.AuxInt
+ if !(d != 0) {
+ break
+ }
+ v.reset(OpConst32)
+ v.AuxInt = int64(int32(c % d))
+ return true
+ }
+ return false
+}
+func rewriteValuegeneric_OpMod32u(v *Value, config *Config) bool {
+ b := v.Block
+ _ = b
+ // match: (Mod32u (Const32 [c]) (Const32 [d]))
+ // cond: d != 0
+ // result: (Const32 [int64(uint32(c) % uint32(d))])
+ for {
+ v_0 := v.Args[0]
+ if v_0.Op != OpConst32 {
+ break
+ }
+ c := v_0.AuxInt
+ v_1 := v.Args[1]
+ if v_1.Op != OpConst32 {
+ break
+ }
+ d := v_1.AuxInt
+ if !(d != 0) {
+ break
+ }
+ v.reset(OpConst32)
+ v.AuxInt = int64(uint32(c) % uint32(d))
+ return true
+ }
+ return false
+}
func rewriteValuegeneric_OpMod64(v *Value, config *Config) bool {
b := v.Block
_ = b
+ // match: (Mod64 (Const64 [c]) (Const64 [d]))
+ // cond: d != 0
+ // result: (Const64 [c % d])
+ for {
+ v_0 := v.Args[0]
+ if v_0.Op != OpConst64 {
+ break
+ }
+ c := v_0.AuxInt
+ v_1 := v.Args[1]
+ if v_1.Op != OpConst64 {
+ break
+ }
+ d := v_1.AuxInt
+ if !(d != 0) {
+ break
+ }
+ v.reset(OpConst64)
+ v.AuxInt = c % d
+ return true
+ }
// match: (Mod64 <t> x (Const64 [c]))
- // cond: smagic64ok(c)
+ // cond: x.Op != OpConst64 && smagic64ok(c)
// result: (Sub64 x (Mul64 <t> (Div64 <t> x (Const64 <t> [c])) (Const64 <t> [c])))
for {
t := v.Type
@@ -4423,7 +4560,7 @@
break
}
c := v_1.AuxInt
- if !(smagic64ok(c)) {
+ if !(x.Op != OpConst64 && smagic64ok(c)) {
break
}
v.reset(OpSub64)
@@ -4446,6 +4583,27 @@
func rewriteValuegeneric_OpMod64u(v *Value, config *Config) bool {
b := v.Block
_ = b
+ // match: (Mod64u (Const64 [c]) (Const64 [d]))
+ // cond: d != 0
+ // result: (Const64 [int64(uint64(c) % uint64(d))])
+ for {
+ v_0 := v.Args[0]
+ if v_0.Op != OpConst64 {
+ break
+ }
+ c := v_0.AuxInt
+ v_1 := v.Args[1]
+ if v_1.Op != OpConst64 {
+ break
+ }
+ d := v_1.AuxInt
+ if !(d != 0) {
+ break
+ }
+ v.reset(OpConst64)
+ v.AuxInt = int64(uint64(c) % uint64(d))
+ return true
+ }
// match: (Mod64u <t> n (Const64 [c]))
// cond: isPowerOfTwo(c)
// result: (And64 n (Const64 <t> [c-1]))
@@ -4468,7 +4626,7 @@
return true
}
// match: (Mod64u <t> x (Const64 [c]))
- // cond: umagic64ok(c)
+ // cond: x.Op != OpConst64 && umagic64ok(c)
// result: (Sub64 x (Mul64 <t> (Div64u <t> x (Const64 <t> [c])) (Const64 <t> [c])))
for {
t := v.Type
@@ -4478,7 +4636,7 @@
break
}
c := v_1.AuxInt
- if !(umagic64ok(c)) {
+ if !(x.Op != OpConst64 && umagic64ok(c)) {
break
}
v.reset(OpSub64)
@@ -4498,6 +4656,58 @@
}
return false
}
+func rewriteValuegeneric_OpMod8(v *Value, config *Config) bool {
+ b := v.Block
+ _ = b
+ // match: (Mod8 (Const8 [c]) (Const8 [d]))
+ // cond: d != 0
+ // result: (Const8 [int64(int8(c % d))])
+ for {
+ v_0 := v.Args[0]
+ if v_0.Op != OpConst8 {
+ break
+ }
+ c := v_0.AuxInt
+ v_1 := v.Args[1]
+ if v_1.Op != OpConst8 {
+ break
+ }
+ d := v_1.AuxInt
+ if !(d != 0) {
+ break
+ }
+ v.reset(OpConst8)
+ v.AuxInt = int64(int8(c % d))
+ return true
+ }
+ return false
+}
+func rewriteValuegeneric_OpMod8u(v *Value, config *Config) bool {
+ b := v.Block
+ _ = b
+ // match: (Mod8u (Const8 [c]) (Const8 [d]))
+ // cond: d != 0
+ // result: (Const8 [int64(uint8(c) % uint8(d))])
+ for {
+ v_0 := v.Args[0]
+ if v_0.Op != OpConst8 {
+ break
+ }
+ c := v_0.AuxInt
+ v_1 := v.Args[1]
+ if v_1.Op != OpConst8 {
+ break
+ }
+ d := v_1.AuxInt
+ if !(d != 0) {
+ break
+ }
+ v.reset(OpConst8)
+ v.AuxInt = int64(uint8(c) % uint8(d))
+ return true
+ }
+ return false
+}
func rewriteValuegeneric_OpMul16(v *Value, config *Config) bool {
b := v.Block
_ = b
