test/codegen: port math/bits.TrailingZeros tests to codegen

And remove them from ssa_test.

Change-Id: Ib5de5c0d908f23915e0847eca338cacf2fa5325b
Reviewed-on: https://go-review.googlesource.com/98795Reviewed-by: Giovanni Bajo <rasky@develer.com>

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

@@ -523,38 +523,6 @@ var linuxAMD64Tests = []*asmTest{
 		pos: []string{"\tBTQ\t\\$60"},
 	},
 	// Intrinsic tests for math/bits
-	{
-		fn: `
-		func f41(a uint64) int {
-			return bits.TrailingZeros64(a)
-		}
-		`,
-		pos: []string{"\tBSFQ\t", "\tMOVL\t\\$64,", "\tCMOVQEQ\t"},
-	},
-	{
-		fn: `
-		func f42(a uint32) int {
-			return bits.TrailingZeros32(a)
-		}
-		`,
-		pos: []string{"\tBSFQ\t", "\tORQ\t[^$]", "\tMOVQ\t\\$4294967296,"},
-	},
-	{
-		fn: `
-		func f43(a uint16) int {
-			return bits.TrailingZeros16(a)
-		}
-		`,
-		pos: []string{"\tBSFQ\t", "\tORQ\t\\$65536,"},
-	},
-	{
-		fn: `
-		func f44(a uint8) int {
-			return bits.TrailingZeros8(a)
-		}
-		`,
-		pos: []string{"\tBSFQ\t", "\tORQ\t\\$256,"},
-	},
 	{
 		fn: `
 		func f45(a uint64) uint64 {
@@ -1230,39 +1198,6 @@ var linuxS390XTests = []*asmTest{
 		pos: []string{"\tFMSUBS\t"},
 	},
 	// Intrinsic tests for math/bits
-	{
-		fn: `
-		func f18(a uint64) int {
-			return bits.TrailingZeros64(a)
-		}
-		`,
-		pos: []string{"\tFLOGR\t"},
-	},
-	{
-		fn: `
-		func f19(a uint32) int {
-			return bits.TrailingZeros32(a)
-		}
-		`,
-		pos: []string{"\tFLOGR\t", "\tMOVWZ\t"},
-	},
-	{
-		fn: `
-		func f20(a uint16) int {
-			return bits.TrailingZeros16(a)
-		}
-		`,
-		pos: []string{"\tFLOGR\t", "\tOR\t\\$65536,"},
-	},
-	{
-		fn: `
-		func f21(a uint8) int {
-			return bits.TrailingZeros8(a)
-		}
-		`,
-		pos: []string{"\tFLOGR\t", "\tOR\t\\$256,"},
-	},
-	// Intrinsic tests for math/bits
 	{
 		fn: `
 		func f22(a uint64) uint64 {

test/codegen/mathbits.go

@@ -95,3 +95,37 @@ func Len8(n uint8) int {
 	//mips:"CLZ"
 	return bits.Len8(n)
 }
+
+// ------------------------ //
+//    bits.TrailingZeros    //
+// ------------------------ //
+
+func TrailingZeros(n uint) int {
+	//amd64:"BSFQ","MOVL\t\\$64","CMOVQEQ"
+	//s390x:"FLOGR"
+	return bits.TrailingZeros(n)
+}
+
+func TrailingZeros64(n uint64) int {
+	//amd64:"BSFQ","MOVL\t\\$64","CMOVQEQ"
+	//s390x:"FLOGR"
+	return bits.TrailingZeros64(n)
+}
+
+func TrailingZeros32(n uint32) int {
+	//amd64:"MOVQ\t\\$4294967296","ORQ\t[^$]","BSFQ"
+	//s390x:"FLOGR","MOVWZ"
+	return bits.TrailingZeros32(n)
+}
+
+func TrailingZeros16(n uint16) int {
+	//amd64:"BSFQ","ORQ\t\\$65536"
+	//s390x:"FLOGR","OR\t\\$65536"
+	return bits.TrailingZeros16(n)
+}
+
+func TrailingZeros8(n uint8) int {
+	//amd64:"BSFQ","ORQ\t\\$256"
+	//s390x:"FLOGR","OR\t\\$256"
+	return bits.TrailingZeros8(n)
+}