compile: Implement while and if

Author: ncw

compile/compile.go

@@ -209,7 +209,7 @@ func (c *compiler) Jump(Op byte, Dest *Label) {
 	switch Op {
 	case vm.JUMP_IF_FALSE_OR_POP, vm.JUMP_IF_TRUE_OR_POP, vm.JUMP_ABSOLUTE, vm.POP_JUMP_IF_FALSE, vm.POP_JUMP_IF_TRUE: // Absolute
 		c.OpCodes.Add(&JumpAbs{OpArg: OpArg{Op: Op}, Dest: Dest})
-	case vm.JUMP_FORWARD: // Relative
+	case vm.JUMP_FORWARD, vm.SETUP_WITH, vm.FOR_ITER, vm.SETUP_LOOP, vm.SETUP_EXCEPT, vm.SETUP_FINALLY:
 		c.OpCodes.Add(&JumpRel{OpArg: OpArg{Op: Op}, Dest: Dest})
 	default:
 		panic("Jump called with non jump instruction")
@@ -314,12 +314,42 @@ func (c *compiler) Stmt(stmt ast.Stmt) {
 		// Test   Expr
 		// Body   []Stmt
 		// Orelse []Stmt
-		panic("FIXME compile: While not implemented")
+		endwhile := new(Label)
+		endpopblock := new(Label)
+		c.Jump(vm.SETUP_LOOP, endpopblock)
+		while := c.NewLabel()
+		c.Expr(node.Test)
+		c.Jump(vm.POP_JUMP_IF_FALSE, endwhile)
+		for _, stmt := range node.Body {
+			c.Stmt(stmt)
+		}
+		c.Jump(vm.JUMP_ABSOLUTE, while)
+		c.Label(endwhile)
+		c.Op(vm.POP_BLOCK)
+		for _, stmt := range node.Orelse {
+			c.Stmt(stmt)
+		}
+		c.Label(endpopblock)
 	case *ast.If:
 		// Test   Expr
 		// Body   []Stmt
 		// Orelse []Stmt
-		panic("FIXME compile: If not implemented")
+		orelse := new(Label)
+		endif := new(Label)
+		c.Expr(node.Test)
+		c.Jump(vm.POP_JUMP_IF_FALSE, orelse)
+		for _, stmt := range node.Body {
+			c.Stmt(stmt)
+		}
+		// FIXME this puts a JUMP_FORWARD in when not
+		// necessary (when no Orelse statements) but it
+		// matches python3.4
+		c.Jump(vm.JUMP_FORWARD, endif)
+		c.Label(orelse)
+		for _, stmt := range node.Orelse {
+			c.Stmt(stmt)
+		}
+		c.Label(endif)
 	case *ast.With:
 		// Items []*WithItem
 		// Body  []Stmt

compile/compile_data_test.go

@@ -1149,7 +1149,7 @@ var compileTestData = []struct {
 		Name:        "<module>",
 		Firstlineno: 1,
 		Lnotab:      "",
-	}, "  1           0 LOAD_CONST               0 (<code object <lambda> at 0x7fd0bed8ee40, file \"<string>\", line 1>)\n              3 LOAD_CONST               1 ('<lambda>')\n              6 MAKE_FUNCTION            0\n              9 RETURN_VALUE\n"},
+	}, "  1           0 LOAD_CONST               0 (<code object <lambda> at 0x7f643912ce40, file \"<string>\", line 1>)\n              3 LOAD_CONST               1 ('<lambda>')\n              6 MAKE_FUNCTION            0\n              9 RETURN_VALUE\n"},
 	{"pass", "exec", &py.Code{
 		Argcount:       0,
 		Kwonlyargcount: 0,
@@ -1575,4 +1575,72 @@ var compileTestData = []struct {
 		Firstlineno:    1,
 		Lnotab:         "",
 	}, "  1           0 LOAD_NAME                0 (a)\n              3 LOAD_NAME                1 (b)\n              6 RAISE_VARARGS            2\n              9 LOAD_CONST               0 (None)\n             12 RETURN_VALUE\n"},
+	{"if a: b = c", "exec", &py.Code{
+		Argcount:       0,
+		Kwonlyargcount: 0,
+		Nlocals:        0,
+		Stacksize:      1,
+		Flags:          64,
+		Code:           "\x65\x00\x00\x72\x0f\x00\x65\x01\x00\x5a\x02\x00\x6e\x00\x00\x64\x00\x00\x53",
+		Consts:         []py.Object{py.None},
+		Names:          []string{"a", "c", "b"},
+		Varnames:       []string{},
+		Freevars:       []string{},
+		Cellvars:       []string{},
+		Filename:       "<string>",
+		Name:           "<module>",
+		Firstlineno:    1,
+		Lnotab:         "\x06\x00",
+	}, "  1           0 LOAD_NAME                0 (a)\n              3 POP_JUMP_IF_FALSE       15\n              6 LOAD_NAME                1 (c)\n              9 STORE_NAME               2 (b)\n             12 JUMP_FORWARD             0 (to 15)\n        >>   15 LOAD_CONST               0 (None)\n             18 RETURN_VALUE\n"},
+	{"if a:\n b = c\nelse:\n c = d\n", "exec", &py.Code{
+		Argcount:       0,
+		Kwonlyargcount: 0,
+		Nlocals:        0,
+		Stacksize:      1,
+		Flags:          64,
+		Code:           "\x65\x00\x00\x72\x0f\x00\x65\x01\x00\x5a\x02\x00\x6e\x06\x00\x65\x03\x00\x5a\x01\x00\x64\x00\x00\x53",
+		Consts:         []py.Object{py.None},
+		Names:          []string{"a", "c", "b", "d"},
+		Varnames:       []string{},
+		Freevars:       []string{},
+		Cellvars:       []string{},
+		Filename:       "<string>",
+		Name:           "<module>",
+		Firstlineno:    1,
+		Lnotab:         "\x06\x01\x09\x02",
+	}, "  1           0 LOAD_NAME                0 (a)\n              3 POP_JUMP_IF_FALSE       15\n\n  2           6 LOAD_NAME                1 (c)\n              9 STORE_NAME               2 (b)\n             12 JUMP_FORWARD             6 (to 21)\n\n  4     >>   15 LOAD_NAME                3 (d)\n             18 STORE_NAME               1 (c)\n        >>   21 LOAD_CONST               0 (None)\n             24 RETURN_VALUE\n"},
+	{"while a:\n b = c", "exec", &py.Code{
+		Argcount:       0,
+		Kwonlyargcount: 0,
+		Nlocals:        0,
+		Stacksize:      1,
+		Flags:          64,
+		Code:           "\x78\x10\x00\x65\x00\x00\x72\x12\x00\x65\x01\x00\x5a\x02\x00\x71\x03\x00\x57\x64\x00\x00\x53",
+		Consts:         []py.Object{py.None},
+		Names:          []string{"a", "c", "b"},
+		Varnames:       []string{},
+		Freevars:       []string{},
+		Cellvars:       []string{},
+		Filename:       "<string>",
+		Name:           "<module>",
+		Firstlineno:    1,
+		Lnotab:         "\x09\x01",
+	}, "  1           0 SETUP_LOOP              16 (to 19)\n        >>    3 LOAD_NAME                0 (a)\n              6 POP_JUMP_IF_FALSE       18\n\n  2           9 LOAD_NAME                1 (c)\n             12 STORE_NAME               2 (b)\n             15 JUMP_ABSOLUTE            3\n        >>   18 POP_BLOCK\n        >>   19 LOAD_CONST               0 (None)\n             22 RETURN_VALUE\n"},
+	{"while a:\n b = c\nelse:\n b = d\n", "exec", &py.Code{
+		Argcount:       0,
+		Kwonlyargcount: 0,
+		Nlocals:        0,
+		Stacksize:      1,
+		Flags:          64,
+		Code:           "\x78\x16\x00\x65\x00\x00\x72\x12\x00\x65\x01\x00\x5a\x02\x00\x71\x03\x00\x57\x65\x03\x00\x5a\x02\x00\x64\x00\x00\x53",
+		Consts:         []py.Object{py.None},
+		Names:          []string{"a", "c", "b", "d"},
+		Varnames:       []string{},
+		Freevars:       []string{},
+		Cellvars:       []string{},
+		Filename:       "<string>",
+		Name:           "<module>",
+		Firstlineno:    1,
+		Lnotab:         "\x09\x01\x0a\x02",
+	}, "  1           0 SETUP_LOOP              22 (to 25)\n        >>    3 LOAD_NAME                0 (a)\n              6 POP_JUMP_IF_FALSE       18\n\n  2           9 LOAD_NAME                1 (c)\n             12 STORE_NAME               2 (b)\n             15 JUMP_ABSOLUTE            3\n        >>   18 POP_BLOCK\n\n  4          19 LOAD_NAME                3 (d)\n             22 STORE_NAME               2 (b)\n        >>   25 LOAD_CONST               0 (None)\n             28 RETURN_VALUE\n"},
 }

compile/make_compile_test.py

@@ -130,7 +130,13 @@
     ('''raise''', "exec"),
     ('''raise a''', "exec"),
     ('''raise a from b''', "exec"),
-    
+    # if
+    ('''if a: b = c''', "exec"),
+    ('''if a:\n b = c\nelse:\n c = d\n''', "exec"),
+    # while
+    ('''while a:\n b = c''', "exec"),
+    ('''while a:\n b = c\nelse:\n b = d\n''', "exec"),
+    # FIXME break
 
 ]