test/codegen: port arm64 BIC/EON/ORN and masking tests

And delete them from asm_test.

Change-Id: I24f421b87e8cb4770c887a6dfd58eacd0088947d
Reviewed-on: https://go-review.googlesource.com/106056Reviewed-by: Keith Randall <khr@golang.org>

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

@@ -283,49 +283,6 @@ var linuxARMTests = []*asmTest{
 }
 
 var linuxARM64Tests = []*asmTest{
-	{
-		fn: `
-		func $(x, y uint32) uint32 {
-			return x &^ y
-		}
-		`,
-		pos: []string{"\tBIC\t"},
-		neg: []string{"\tAND\t"},
-	},
-	{
-		fn: `
-		func $(x, y uint32) uint32 {
-			return x ^ ^y
-		}
-		`,
-		pos: []string{"\tEON\t"},
-		neg: []string{"\tXOR\t"},
-	},
-	{
-		fn: `
-		func $(x, y uint32) uint32 {
-			return x | ^y
-		}
-		`,
-		pos: []string{"\tORN\t"},
-		neg: []string{"\tORR\t"},
-	},
-	{
-		fn: `
-		func f34(a uint64) uint64 {
-			return a & ((1<<63)-1)
-		}
-		`,
-		pos: []string{"\tAND\t"},
-	},
-	{
-		fn: `
-		func f35(a uint64) uint64 {
-			return a & (1<<63)
-		}
-		`,
-		pos: []string{"\tAND\t"},
-	},
 	// Load-combining tests.
 	{
 		fn: `

test/codegen/bits.go

@@ -261,3 +261,32 @@ func bitcompl32(a, b uint32) (n uint32) {
 
 	return n
 }
+
+// Check AND masking on arm64 (Issue #19857)
+
+func and_mask_1(a uint64) uint64 {
+	// arm64:`AND\t`
+	return a & ((1 << 63) - 1)
+}
+
+func and_mask_2(a uint64) uint64 {
+	// arm64:`AND\t`
+	return a & (1 << 63)
+}
+
+// Check generation of arm64 BIC/EON/ORN instructions
+
+func op_bic(x, y uint32) uint32 {
+	// arm64:`BIC\t`,-`AND`
+	return x &^ y
+}
+
+func op_eon(x, y uint32) uint32 {
+	// arm64:`EON\t`,-`XOR`
+	return x ^ ^y
+}
+
+func op_orn(x, y uint32) uint32 {
+	// arm64:`ORN\t`,-`ORR`
+	return x | ^y
+}