cmd/gc: don't squash complex literals when inlining.

Since this patch changes the way complex literals are written
in export data, there are a few other glitches.

Fixes #4159.

R=golang-dev, rsc
CC=golang-dev, remy
https://golang.org/cl/6674047

src/cmd/gc/fmt.c

@@ -379,7 +379,7 @@ Vconv(Fmt *fp)
 		return fmtprint(fp, "%#F", v->u.fval);
 	case CTCPLX:
 		if((fp->flags & FmtSharp) || fmtmode == FExp)
-			return fmtprint(fp, "(%F+%F)", &v->u.cval->real, &v->u.cval->imag);
+			return fmtprint(fp, "(%F+%Fi)", &v->u.cval->real, &v->u.cval->imag);
 		return fmtprint(fp, "(%#F + %#Fi)", &v->u.cval->real, &v->u.cval->imag);
 	case CTSTR:
 		return fmtprint(fp, "\"%Z\"", v->u.sval);

src/cmd/gc/go.y

@@ -2039,6 +2039,8 @@ hidden_constant:
 			mpaddfixfix($2->val.u.xval, $4->val.u.xval, 0);
 			break;
 		}
+		$4->val.u.cval->real = $4->val.u.cval->imag;
+		mpmovecflt(&$4->val.u.cval->imag, 0.0);
 		$$ = nodcplxlit($2->val, $4->val);
 	}
 

src/cmd/gc/y.tab.h

-/* A Bison parser, made by GNU Bison 2.5.  */
+/* A Bison parser, made by GNU Bison 2.6.2.  */
 
 /* Bison interface for Yacc-like parsers in C
    
-      Copyright (C) 1984, 1989-1990, 2000-2011 Free Software Foundation, Inc.
+      Copyright (C) 1984, 1989-1990, 2000-2012 Free Software Foundation, Inc.
    
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -30,6 +30,15 @@
    This special exception was added by the Free Software Foundation in
    version 2.2 of Bison.  */
 
+#ifndef YY_Y_TAB_H
+# define YY_Y_TAB_H
+/* Enabling traces.  */
+#ifndef YYDEBUG
+# define YYDEBUG 0
+#endif
+#if YYDEBUG
+extern int yydebug;
+#endif
 
 /* Tokens.  */
 #ifndef YYTOKENTYPE
@@ -141,12 +150,10 @@
 
 
 
-
 #if ! defined YYSTYPE && ! defined YYSTYPE_IS_DECLARED
 typedef union YYSTYPE
 {
-
-/* Line 2068 of yacc.c  */
+/* Line 2049 of yacc.c  */
 #line 28 "go.y"
 
 	Node*		node;
@@ -157,9 +164,8 @@ typedef union YYSTYPE
 	int		i;
 
 
-
-/* Line 2068 of yacc.c  */
-#line 163 "y.tab.h"
+/* Line 2049 of yacc.c  */
+#line 169 "y.tab.h"
 } YYSTYPE;
 # define YYSTYPE_IS_TRIVIAL 1
 # define yystype YYSTYPE /* obsolescent; will be withdrawn */
@@ -168,4 +174,18 @@ typedef union YYSTYPE
 
 extern YYSTYPE yylval;
 
+#ifdef YYPARSE_PARAM
+#if defined __STDC__ || defined __cplusplus
+int yyparse (void *YYPARSE_PARAM);
+#else
+int yyparse ();
+#endif
+#else /* ! YYPARSE_PARAM */
+#if defined __STDC__ || defined __cplusplus
+int yyparse (void);
+#else
+int yyparse ();
+#endif
+#endif /* ! YYPARSE_PARAM */
 
+#endif /* !YY_Y_TAB_H  */

src/pkg/exp/types/gcimporter.go

@@ -681,7 +681,7 @@ func (p *gcParser) parseNumber() Const {
 // ConstDecl   = "const" ExportedName [ Type ] "=" Literal .
 // Literal     = bool_lit | int_lit | float_lit | complex_lit | string_lit .
 // bool_lit    = "true" | "false" .
-// complex_lit = "(" float_lit "+" float_lit ")" .
+// complex_lit = "(" float_lit "+" float_lit "i" ")" .
 // rune_lit = "(" int_lit "+" int_lit ")" .
 // string_lit  = `"` { unicode_char } `"` .
 //
@@ -725,6 +725,7 @@ func (p *gcParser) parseConstDecl() {
 		re := p.parseNumber()
 		p.expect('+')
 		im := p.parseNumber()
+		p.expectKeyword("i")
 		p.expect(')')
 		x = Const{cmplx{re.val.(*big.Rat), im.val.(*big.Rat)}}
 		typ = Complex128.Underlying

src/pkg/exp/types/staging/gcimporter.go

@@ -687,7 +687,7 @@ func (p *gcParser) parseNumber() (x operand) {
 // ConstDecl   = "const" ExportedName [ Type ] "=" Literal .
 // Literal     = bool_lit | int_lit | float_lit | complex_lit | rune_lit | string_lit .
 // bool_lit    = "true" | "false" .
-// complex_lit = "(" float_lit "+" float_lit ")" .
+// complex_lit = "(" float_lit "+" float_lit "i" ")" .
 // rune_lit = "(" int_lit "+" int_lit ")" .
 // string_lit  = `"` { unicode_char } `"` .
 //
@@ -728,6 +728,7 @@ func (p *gcParser) parseConstDecl() {
 		re := p.parseNumber()
 		p.expect('+')
 		im := p.parseNumber()
+		p.expectKeyword("i")
 		p.expect(')')
 		x.typ = Typ[UntypedComplex]
 		// TODO(gri) fix this

test/fixedbugs/bug466.dir/a.go

+// Copyright 2012 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 a
+
+const N = 2+3i
+
+func Func() []complex128 {
+	return []complex128{1, complex(2, 3), complex(4, 5)}
+}
+
+func Mul(z complex128) complex128 {
+	return z * (3 + 4i)
+}

test/fixedbugs/bug466.dir/b.go

+// Copyright 2012 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 main
+
+import "./a"
+
+func main() {
+	s := a.Func()
+	if s[0] != 1 {
+		println(s[0])
+		panic("s[0] != 1")
+	}
+	if s[1] != 2+3i {
+		println(s[1])
+		panic("s[1] != 2+3i")
+	}
+	if s[2] != 4+5i {
+		println(s[2])
+		panic("s[2] != 4+5i")
+	}
+
+	x := 1 + 2i
+	y := a.Mul(x)
+	if y != (1+2i)*(3+4i) {
+		println(y)
+		panic("y != (1+2i)*(3+4i)")
+	}
+}

test/fixedbugs/bug466.go

+// rundir
+
+// Copyright 2012 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.
+
+// Issue 4159: exported inlinable functions squash
+// complex literals "a+bi" to "a+b".
+
+package ignored
+