test: port bits.Len intrinsics tests to the new codegen harness

This change move bits.Len* intrinsification tests to the new codegen
test harness, removing them from the old ssa_test file. Five different
test functions (one for each bit.Len function tested) was used, to
avoid possible unwanted interactions between multiple calls inside one
function.

Change-Id: Iffd5be55b58e88597fa30a562a28dacb01236d8b
Reviewed-on: https://go-review.googlesource.com/98156
Run-TryBot: Alberto Donizetti <alb.donizetti@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Giovanni Bajo <rasky@develer.com>

src/cmd/compile/internal/gc/asm_test.go

@@ -580,48 +580,6 @@ var linuxAMD64Tests = []*asmTest{
 		`,
 		pos: []string{"\tROLW\t\\$8,"},
 	},
-	{
-		fn: `
-		func f48(a uint64) int {
-			return bits.Len64(a)
-		}
-		`,
-		pos: []string{"\tBSRQ\t"},
-	},
-	{
-		fn: `
-		func f49(a uint32) int {
-			return bits.Len32(a)
-		}
-		`,
-		pos: []string{"\tBSRQ\t"},
-	},
-	{
-		fn: `
-		func f50(a uint16) int {
-			return bits.Len16(a)
-		}
-		`,
-		pos: []string{"\tBSRQ\t"},
-	},
-	/* see ssa.go
-	{
-		fn:`
-		func f51(a uint8) int {
-			return bits.Len8(a)
-		}
-		`,
-		pos:[]string{"\tBSRQ\t"},
-	},
-	*/
-	{
-		fn: `
-		func f52(a uint) int {
-			return bits.Len(a)
-		}
-		`,
-		pos: []string{"\tBSRQ\t"},
-	},
 	{
 		fn: `
 		func f53(a uint64) int {
@@ -1364,46 +1322,6 @@ var linuxS390XTests = []*asmTest{
 		`,
 		pos: []string{"\tMOVWBR\t"},
 	},
-	{
-		fn: `
-		func f24(a uint64) int {
-			return bits.Len64(a)
-		}
-		`,
-		pos: []string{"\tFLOGR\t"},
-	},
-	{
-		fn: `
-		func f25(a uint32) int {
-			return bits.Len32(a)
-		}
-		`,
-		pos: []string{"\tFLOGR\t"},
-	},
-	{
-		fn: `
-		func f26(a uint16) int {
-			return bits.Len16(a)
-		}
-		`,
-		pos: []string{"\tFLOGR\t"},
-	},
-	{
-		fn: `
-		func f27(a uint8) int {
-			return bits.Len8(a)
-		}
-		`,
-		pos: []string{"\tFLOGR\t"},
-	},
-	{
-		fn: `
-		func f28(a uint) int {
-			return bits.Len(a)
-		}
-		`,
-		pos: []string{"\tFLOGR\t"},
-	},
 	{
 		fn: `
 		func f29(a uint64) int {
@@ -1501,46 +1419,6 @@ var linuxARMTests = []*asmTest{
 		`,
 		pos: []string{"\tMOVW\tR[0-9]+@>25,"},
 	},
-	{
-		fn: `
-		func f3(a uint64) int {
-			return bits.Len64(a)
-		}
-		`,
-		pos: []string{"\tCLZ\t"},
-	},
-	{
-		fn: `
-		func f4(a uint32) int {
-			return bits.Len32(a)
-		}
-		`,
-		pos: []string{"\tCLZ\t"},
-	},
-	{
-		fn: `
-		func f5(a uint16) int {
-			return bits.Len16(a)
-		}
-		`,
-		pos: []string{"\tCLZ\t"},
-	},
-	{
-		fn: `
-		func f6(a uint8) int {
-			return bits.Len8(a)
-		}
-		`,
-		pos: []string{"\tCLZ\t"},
-	},
-	{
-		fn: `
-		func f7(a uint) int {
-			return bits.Len(a)
-		}
-		`,
-		pos: []string{"\tCLZ\t"},
-	},
 	{
 		fn: `
 		func f8(a uint64) int {
@@ -1715,46 +1593,6 @@ var linuxARM64Tests = []*asmTest{
 		`,
 		pos: []string{"\tREVW\t"},
 	},
-	{
-		fn: `
-		func f24(a uint64) int {
-			return bits.Len64(a)
-		}
-		`,
-		pos: []string{"\tCLZ\t"},
-	},
-	{
-		fn: `
-		func f25(a uint32) int {
-			return bits.Len32(a)
-		}
-		`,
-		pos: []string{"\tCLZ\t"},
-	},
-	{
-		fn: `
-		func f26(a uint16) int {
-			return bits.Len16(a)
-		}
-		`,
-		pos: []string{"\tCLZ\t"},
-	},
-	{
-		fn: `
-		func f27(a uint8) int {
-			return bits.Len8(a)
-		}
-		`,
-		pos: []string{"\tCLZ\t"},
-	},
-	{
-		fn: `
-		func f28(a uint) int {
-			return bits.Len(a)
-		}
-		`,
-		pos: []string{"\tCLZ\t"},
-	},
 	{
 		fn: `
 		func f29(a uint64) int {
@@ -2177,46 +2015,6 @@ var linuxARM64Tests = []*asmTest{
 
 var linuxMIPSTests = []*asmTest{
 	// Intrinsic tests for math/bits
-	{
-		fn: `
-		func f0(a uint64) int {
-			return bits.Len64(a)
-		}
-		`,
-		pos: []string{"\tCLZ\t"},
-	},
-	{
-		fn: `
-		func f1(a uint32) int {
-			return bits.Len32(a)
-		}
-		`,
-		pos: []string{"\tCLZ\t"},
-	},
-	{
-		fn: `
-		func f2(a uint16) int {
-			return bits.Len16(a)
-		}
-		`,
-		pos: []string{"\tCLZ\t"},
-	},
-	{
-		fn: `
-		func f3(a uint8) int {
-			return bits.Len8(a)
-		}
-		`,
-		pos: []string{"\tCLZ\t"},
-	},
-	{
-		fn: `
-		func f4(a uint) int {
-			return bits.Len(a)
-		}
-		`,
-		pos: []string{"\tCLZ\t"},
-	},
 	{
 		fn: `
 		func f5(a uint64) int {

test/codegen/mathbits.go

+// asmcheck
+
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package codegen
+
+import "math/bits"
+
+// --------------- //
+//    bits.Len*    //
+// --------------- //
+
+func Len(n uint) int {
+	//amd64:"BSRQ"
+	//s390x:"FLOGR"
+	//arm:"CLZ" arm64:"CLZ"
+	//mips:"CLZ"
+	return bits.Len(n)
+}
+
+func Len64(n uint64) int {
+	//amd64:"BSRQ"
+	//s390x:"FLOGR"
+	//arm:"CLZ" arm64:"CLZ"
+	//mips:"CLZ"
+	return bits.Len64(n)
+}
+
+func Len32(n uint32) int {
+	//amd64:"BSRQ"
+	//s390x:"FLOGR"
+	//arm:"CLZ" arm64:"CLZ"
+	//mips:"CLZ"
+	return bits.Len32(n)
+}
+
+func Len16(n uint16) int {
+	//amd64:"BSRQ"
+	//s390x:"FLOGR"
+	//arm:"CLZ" arm64:"CLZ"
+	//mips:"CLZ"
+	return bits.Len16(n)
+}
+
+func Len8(n uint8) int {
+	//amd64 Len8 not intrisified
+	//s390x:"FLOGR"
+	//arm:"CLZ" arm64:"CLZ"
+	//mips:"CLZ"
+	return bits.Len8(n)
+}