pkg/compiler: add builtin bool type aliases

This adds builtin:

type bool8 int8[0:1]
type bool16 int16[0:1]
type bool32 int32[0:1]
type bool64 int64[0:1]
type boolptr intptr[0:1]

We used to use just int's for bools.
But bool types provide several advantages:
 - make true/false probability equal
 - improve description expressiveness
 - reduce search space (we will take advantage of this later)

5 files changed, 37 insertions, 12 deletions

diff --git a/pkg/ast/testdata/all.txt b/pkg/ast/testdata/all.txt
index fedcc51a2..268b49a47 100644
--- a/pkg/ast/testdata/all.txt
+++ b/pkg/ast/testdata/all.txt
@@ -46,7 +46,7 @@ s2 {
 
 }
 
-type bool8 int8
+type mybool8 int8
 type net_port proc[1, 2, int16be]
-type bool16				### unexpected '\n', expecting int, identifier, string
+type mybool16				### unexpected '\n', expecting int, identifier, string
 type type4:4 int32			### unexpected ':', expecting int, identifier, string
diff --git a/pkg/compiler/check.go b/pkg/compiler/check.go
index ff87ead79..e9ec872f5 100644
--- a/pkg/compiler/check.go
+++ b/pkg/compiler/check.go
@@ -40,7 +40,7 @@ func (comp *compiler) checkNames() {
 				comp.error(pos, "%v uses reserved name %v", typ, name)
 				continue
 			}
-			if builtinTypes[name] != nil {
+			if builtinTypes[name] != nil || builtinTypedefs[name] != nil {
 				comp.error(pos, "%v name %v conflicts with builtin type", typ, name)
 				continue
 			}
diff --git a/pkg/compiler/compiler.go b/pkg/compiler/compiler.go
index 0be7f2817..3901747a6 100644
--- a/pkg/compiler/compiler.go
+++ b/pkg/compiler/compiler.go
@@ -62,6 +62,9 @@ func Compile(desc *ast.Description, consts map[string]uint64, target *targets.Ta
 		structNodes:  make(map[*prog.StructDesc]*ast.Struct),
 		structVarlen: make(map[string]bool),
 	}
+	for name, typedef := range builtinTypedefs {
+		comp.typedefs[name] = typedef
+	}
 	comp.assignSyscallNumbers(consts)
 	comp.patchConsts(consts)
 	comp.check()
diff --git a/pkg/compiler/testdata/errors.txt b/pkg/compiler/testdata/errors.txt
index 237519aa3..0a9363924 100644
--- a/pkg/compiler/testdata/errors.txt
+++ b/pkg/compiler/testdata/errors.txt
@@ -181,17 +181,17 @@ define d3 1
 
 # Type aliases.
 
-type bool8 int8[0:1]
-type bool16 int16[0:1]
+type mybool8 int8[0:1]
+type mybool16 int16[0:1]
 type net_port proc[100, 1, int16be]
-resource typeres0[bool8]
+resource typeres0[mybool8]
 typestruct {
-	f1	bool8
-	f2	bool16
+	f1	mybool8
+	f2	mybool16
 }
 typeunion [
-	f1	bool8
-	f2	bool16
+	f1	mybool8
+	f2	mybool16
 ]
 
 type type0 int8
@@ -217,6 +217,7 @@ type type13 ptr[in, typestruct13]
 type type14 flags[type0, int32]
 type type15 const[0, type0]	### unexpected value type0 for base type argument of const type, expect [int8 int16 int32 int64 int16be int32be int64be intptr]
 type type16 ptr[in, type0]	### type aliases can't refer to other type aliases
+type bool8 int8[0:1]		### type name bool8 conflicts with builtin type
 
 typestruct11 {
 	f	type11		### unknown type type11
@@ -231,7 +232,7 @@ typestruct13 {
 	f2	type12
 }
 
-foo$100(a bool8, b bool16)
+foo$100(a mybool8, b mybool16)
 foo$101(a type5)		### unknown type type5
 foo$102(a type2)		### unknown type type2
 foo$103(a type0:4)		### type alias type0 with ':'
diff --git a/pkg/compiler/types.go b/pkg/compiler/types.go
index 6174bb193..ee6e4a559 100644
--- a/pkg/compiler/types.go
+++ b/pkg/compiler/types.go
@@ -638,7 +638,8 @@ var typeArgBase = namedArg{
 }
 
 var (
-	builtinTypes = make(map[string]*typeDesc)
+	builtinTypes    = make(map[string]*typeDesc)
+	builtinTypedefs = make(map[string]*ast.TypeDef)
 
 	// To avoid weird cases like ptr[in, in] and ptr[out, opt].
 	reservedName = map[string]bool{
@@ -649,6 +650,14 @@ var (
 	}
 )
 
+const builtinDefs = `
+type bool8 int8[0:1]
+type bool16 int16[0:1]
+type bool32 int32[0:1]
+type bool64 int64[0:1]
+type boolptr intptr[0:1]
+`
+
 func init() {
 	builtins := []*typeDesc{
 		typeInt,
@@ -674,4 +683,16 @@ func init() {
 			builtinTypes[name] = desc
 		}
 	}
+	builtinDesc := ast.Parse([]byte(builtinDefs), "builtins", func(pos ast.Pos, msg string) {
+		panic(fmt.Sprintf("failed to parse builtins: %v: %v", pos, msg))
+	})
+	for _, decl := range builtinDesc.Nodes {
+		switch n := decl.(type) {
+		case *ast.TypeDef:
+			builtinTypedefs[n.Name.Name] = n
+		case *ast.NewLine:
+		default:
+			panic(fmt.Sprintf("unexpected node in builtins: %#v", n))
+		}
+	}
 }