Implement __typeof__.

5 files changed, 85 insertions, 0 deletions

diff --git a/decl.c b/decl.c
index 870d72a..7bd2cbb 100644
--- a/decl.c
+++ b/decl.c
@@ -325,6 +325,15 @@ declspecs(struct scope *s, enum storageclass *sc, enum funcspecifier *fs, int *a
 			++ntypes;
 			next();
 			break;
+		case T__TYPEOF__:
+			next();
+			expect(TLPAREN, "after '__typeof__'");
+			t = typename(s);
+			if (!t)
+				t = expr(s)->type;
+			++ntypes;
+			expect(TRPAREN, "to close '__typeof__'");
+			break;
 
 		/* 6.7.5 Alignment specifier */
 		case T_ALIGNAS:
diff --git a/pp.c b/pp.c
index 3cb4244..2c47d59 100644
--- a/pp.c
+++ b/pp.c
@@ -27,6 +27,7 @@ keyword(struct token *tok)
 		{"_Noreturn",      T_NORETURN},
 		{"_Static_assert", T_STATIC_ASSERT},
 		{"_Thread_local",  T_THREAD_LOCAL},
+		{"__typeof__",     T__TYPEOF__},
 		{"auto",           TAUTO},
 		{"break",          TBREAK},
 		{"case",           TCASE},
diff --git a/tests/typeof.c b/tests/typeof.c
new file mode 100644
index 0000000..d6a218f
--- /dev/null
+++ b/tests/typeof.c
@@ -0,0 +1,20 @@
+int v;
+typedef int* t;
+int f() {v = 1; return 0;}
+int main() {
+  __typeof__(f()) x = 123;
+  __typeof__(t) y = &x;
+
+  if (x != 123)
+    return 1;
+  if (*y != 123)
+    return 2;
+  if (sizeof(y) != sizeof(int*))
+    return 3;
+  if (sizeof(x) != sizeof(int))
+    return 4;
+  if (v != 0)
+    return 5;
+
+  return 0;
+}
diff --git a/tests/typeof.qbe b/tests/typeof.qbe
new file mode 100644
index 0000000..5cd138f
--- /dev/null
+++ b/tests/typeof.qbe
@@ -0,0 +1,54 @@
+export
+function w $f() {
+@start.1
+@body.2
+	storew 1, $v
+	ret 0
+}
+export
+function w $main() {
+@start.3
+	%.1 =l alloc4 4
+	%.3 =l alloc8 8
+@body.4
+	%.2 =l add %.1, 0
+	storew 123, %.2
+	%.4 =l add %.3, 0
+	storel %.1, %.4
+	%.5 =w loadsw %.1
+	%.6 =w cnew %.5, 123
+	%.7 =w cnew %.6, 0
+	jnz %.7, @if_true.5, @if_false.6
+@if_true.5
+	ret 1
+@if_false.6
+	%.8 =l loadl %.3
+	%.9 =w loadsw %.8
+	%.10 =w cnew %.9, 123
+	%.11 =w cnew %.10, 0
+	jnz %.11, @if_true.7, @if_false.8
+@if_true.7
+	ret 2
+@if_false.8
+	%.12 =w cnel 8, 8
+	%.13 =w cnew %.12, 0
+	jnz %.13, @if_true.9, @if_false.10
+@if_true.9
+	ret 3
+@if_false.10
+	%.14 =w cnel 4, 4
+	%.15 =w cnew %.14, 0
+	jnz %.15, @if_true.11, @if_false.12
+@if_true.11
+	ret 4
+@if_false.12
+	%.16 =w loadsw $v
+	%.17 =w cnew %.16, 0
+	%.18 =w cnew %.17, 0
+	jnz %.18, @if_true.13, @if_false.14
+@if_true.13
+	ret 5
+@if_false.14
+	ret 0
+}
+export data $v = align 4 { z 4 }
diff --git a/token.h b/token.h
index ed4483c..ad19311 100644
--- a/token.h
+++ b/token.h
@@ -54,6 +54,7 @@ enum tokenkind {
 	T_NORETURN,
 	T_STATIC_ASSERT,
 	T_THREAD_LOCAL,
+	T__TYPEOF__,
 
 	/* punctuator */
 	TLBRACK,