Add binary decoding for floats

bench_test.go

@@ -11,6 +11,8 @@ var narrowTestDataLoaded bool
 var int2TextVsBinaryTestDataLoaded bool
 var int4TextVsBinaryTestDataLoaded bool
 var int8TextVsBinaryTestDataLoaded bool
+var float4TextVsBinaryTestDataLoaded bool
+var float8TextVsBinaryTestDataLoaded bool
 
 func mustPrepare(b *testing.B, conn *Connection, name, sql string) {
 	if err := conn.Prepare(name, sql); err != nil {
@@ -407,3 +409,123 @@ func BenchmarkInt8Binary(b *testing.B) {
 		}
 	}
 }
+
+func createFloat4TextVsBinaryTestData(b *testing.B, conn *Connection) {
+	if float4TextVsBinaryTestDataLoaded {
+		return
+	}
+
+	if _, err := conn.Execute(`
+		drop table if exists t;
+
+		create temporary table t(
+			a float4 not null,
+			b float4 not null,
+			c float4 not null,
+			d float4 not null,
+			e float4 not null
+		);
+
+		insert into t(a, b, c, d, e)
+		select
+			(random() * 1000000)::float4, (random() * 1000000)::float4, (random() * 1000000)::float4, (random() * 1000000)::float4, (random() * 1000000)::float4
+		from generate_series(1, 10);
+	`); err != nil {
+		b.Fatalf("Could not set up test data: %v", err)
+	}
+
+	float4TextVsBinaryTestDataLoaded = true
+}
+
+func BenchmarkFloat4Text(b *testing.B) {
+	conn := getSharedConnection()
+	createFloat4TextVsBinaryTestData(b, conn)
+
+	binaryDecoder := valueTranscoders[oid(700)].DecodeBinary
+	valueTranscoders[oid(700)].DecodeBinary = nil
+	defer func() { valueTranscoders[oid(700)].DecodeBinary = binaryDecoder }()
+
+	mustPrepare(b, conn, "selectFloat32", "select * from t")
+	defer func() { conn.Deallocate("selectFloat32") }()
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		if _, err := conn.SelectRows("selectFloat32"); err != nil {
+			b.Fatalf("Failure while benchmarking: %v", err)
+		}
+	}
+}
+
+func BenchmarkFloat4Binary(b *testing.B) {
+	conn := getSharedConnection()
+	createFloat4TextVsBinaryTestData(b, conn)
+	mustPrepare(b, conn, "selectFloat32", "select * from t")
+	defer func() { conn.Deallocate("selectFloat32") }()
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		if _, err := conn.SelectRows("selectFloat32"); err != nil {
+			b.Fatalf("Failure while benchmarking: %v", err)
+		}
+	}
+}
+
+func createFloat8TextVsBinaryTestData(b *testing.B, conn *Connection) {
+	if float8TextVsBinaryTestDataLoaded {
+		return
+	}
+
+	if _, err := conn.Execute(`
+		drop table if exists t;
+
+		create temporary table t(
+			a float8 not null,
+			b float8 not null,
+			c float8 not null,
+			d float8 not null,
+			e float8 not null
+		);
+
+		insert into t(a, b, c, d, e)
+		select
+			(random() * 1000000)::float8, (random() * 1000000)::float8, (random() * 1000000)::float8, (random() * 1000000)::float8, (random() * 1000000)::float8
+		from generate_series(1, 10);
+	`); err != nil {
+		b.Fatalf("Could not set up test data: %v", err)
+	}
+
+	float8TextVsBinaryTestDataLoaded = true
+}
+
+func BenchmarkFloat8Text(b *testing.B) {
+	conn := getSharedConnection()
+	createFloat8TextVsBinaryTestData(b, conn)
+
+	binaryDecoder := valueTranscoders[oid(701)].DecodeBinary
+	valueTranscoders[oid(701)].DecodeBinary = nil
+	defer func() { valueTranscoders[oid(701)].DecodeBinary = binaryDecoder }()
+
+	mustPrepare(b, conn, "selectFloat32", "select * from t")
+	defer func() { conn.Deallocate("selectFloat32") }()
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		if _, err := conn.SelectRows("selectFloat32"); err != nil {
+			b.Fatalf("Failure while benchmarking: %v", err)
+		}
+	}
+}
+
+func BenchmarkFloat8Binary(b *testing.B) {
+	conn := getSharedConnection()
+	createFloat8TextVsBinaryTestData(b, conn)
+	mustPrepare(b, conn, "selectFloat32", "select * from t")
+	defer func() { conn.Deallocate("selectFloat32") }()
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		if _, err := conn.SelectRows("selectFloat32"); err != nil {
+			b.Fatalf("Failure while benchmarking: %v", err)
+		}
+	}
+}

value_transcoder.go

@@ -4,6 +4,7 @@ import (
 	"encoding/hex"
 	"fmt"
 	"strconv"
+	"unsafe"
 )
 
 type valueTranscoder struct {
@@ -58,13 +59,15 @@ func init() {
 
 	// float4
 	valueTranscoders[oid(700)] = &valueTranscoder{
-		DecodeText: decodeFloat4FromText,
-		EncodeTo:   encodeFloat4}
+		DecodeText:   decodeFloat4FromText,
+		DecodeBinary: decodeFloat4FromBinary,
+		EncodeTo:     encodeFloat4}
 
 	// float8
 	valueTranscoders[oid(701)] = &valueTranscoder{
-		DecodeText: decodeFloat8FromText,
-		EncodeTo:   encodeFloat8}
+		DecodeText:   decodeFloat8FromText,
+		DecodeBinary: decodeFloat8FromBinary,
+		EncodeTo:     encodeFloat8}
 
 	// varchar -- same as text
 	valueTranscoders[oid(1043)] = valueTranscoders[oid(25)]
@@ -167,6 +170,16 @@ func decodeFloat4FromText(mr *MessageReader, size int32) interface{} {
 	return float32(n)
 }
 
+func decodeFloat4FromBinary(mr *MessageReader, size int32) interface{} {
+	if size != 4 {
+		panic("Received an invalid size for an float4")
+	}
+
+	i := mr.ReadInt32()
+	p := unsafe.Pointer(&i)
+	return *(*float32)(p)
+}
+
 func encodeFloat4(w *messageWriter, value interface{}) {
 	v := value.(float32)
 	s := strconv.FormatFloat(float64(v), 'e', -1, 32)
@@ -183,6 +196,16 @@ func decodeFloat8FromText(mr *MessageReader, size int32) interface{} {
 	return v
 }
 
+func decodeFloat8FromBinary(mr *MessageReader, size int32) interface{} {
+	if size != 8 {
+		panic("Received an invalid size for an float4")
+	}
+
+	i := mr.ReadInt64()
+	p := unsafe.Pointer(&i)
+	return *(*float64)(p)
+}
+
 func encodeFloat8(w *messageWriter, value interface{}) {
 	v := value.(float64)
 	s := strconv.FormatFloat(float64(v), 'e', -1, 64)