Updates to Switch expr

frontends/p4/typeChecking/typeCheckStmt.cpp

@@ -48,6 +48,14 @@ const IR::Node *TypeInferenceBase::postorder(const IR::SwitchStatement *stat) {
         }
     } else {
         // switch (expression)
+        if (!(type->is<IR::Type_Bits>() || type->is<IR::Type_InfInt>() ||
+              type->is<IR::Type_Enum>() || type->is<IR::Type_SerEnum>() ||
+              type->is<IR::Type_Error>())) {
+            typeError("%1%: switch expression cannot be of type %2%", stat->expression,
+                      type->toString());
+            return stat;
+        }
+
         Comparison comp;
         comp.left = stat->expression;
 

testdata/p4_16_errors/issue5120.p4

@@ -0,0 +1,43 @@
+@command_line("--preferSwitch")
+
+extern void __e(in bit<28> arg);
+extern void __e2(in bit<28> arg);
+
+control C() {
+	action bar(bool a, bool b) {
+		bit<28> x; bit<28> y;
+		switch (a) {
+		b: {
+				__e(x);
+			}
+		default: {
+			if (b) {
+				__e2(y);
+			}
+			}
+		}
+	}
+
+	action baz() {
+		bar(true, false);
+    }
+
+	action foo() {
+		baz();
+
+	}
+
+	table t {
+		actions = { foo; }
+		default_action = foo;
+	}
+
+	apply {
+		t.apply();
+	}
+}
+
+control proto();
+package top(proto p);
+
+top(C()) main;

testdata/p4_16_errors/issue5313_type_variable.p4

@@ -0,0 +1,32 @@
+@command_line("--preferSwitch")
+
+// Generic helper over a type variable T.
+// The switch is written in terms of T; T is instantiated later.
+void bar_generic<T>(T v, out bit<8> y) {
+    switch (v) {
+        0b01: { y = 1; }
+        0b10: { y = 2; }
+        default: { y = 0; }
+    }
+}
+
+control C(out bit<8> y) {
+    action foo() {
+        // Here T is instantiated as bit<2>, so switch(v) is on bit<2>.
+        bar_generic<bit<2>>(1, y);
+    }
+
+    table t {
+        actions = { foo; }
+        default_action = foo;
+    }
+
+    apply {
+        t.apply();
+    }
+}
+
+control proto(out bit<8> y);
+package top(proto p);
+
+top(C()) main;

testdata/p4_16_errors/issue5313_typealiass.p4

@@ -0,0 +1,32 @@
+@command_line("--preferSwitch")
+
+type bit<2> TwoBitsAlias;
+
+void bar(bit<2> x, out bit<8> y) {
+ TwoBitsAlias a = (TwoBitsAlias)x;
+    switch (a) {
+        0b01: { y = 4; }
+        0b10: { y = 5; }
+        default: { y = y; }
+    }
+}
+
+control C(out bit<8> y) {
+    action foo() {
+        bar(1, y);
+    }
+
+    table t {
+        actions = { foo; }
+        default_action = foo;
+    }
+
+    apply {
+        t.apply();
+    }
+}
+
+control proto(out bit<8> y);
+package top(proto p);
+
+top(C()) main;

testdata/p4_16_errors_outputs/issue5120.p4

@@ -0,0 +1,37 @@
+@command_line("--preferSwitch") extern void __e(in bit<28> arg);
+extern void __e2(in bit<28> arg);
+control C() {
+    action bar(bool a, bool b) {
+        bit<28> x;
+        bit<28> y;
+        switch (a) {
+            b: {
+                __e(x);
+            }
+            default: {
+                if (b) {
+                    __e2(y);
+                }
+            }
+        }
+    }
+    action baz() {
+        bar(true, false);
+    }
+    action foo() {
+        baz();
+    }
+    table t {
+        actions = {
+            foo;
+        }
+        default_action = foo;
+    }
+    apply {
+        t.apply();
+    }
+}
+
+control proto();
+package top(proto p);
+top(C()) main;

testdata/p4_16_errors_outputs/issue5120.p4-stderr

@@ -0,0 +1,3 @@
+issue5120.p4(9): [--Werror=type-error] error: a: switch expression cannot be of type bool
+  switch (a) {
+          ^

testdata/p4_16_errors_outputs/issue5313_type_variable.p4

@@ -0,0 +1,31 @@
+@command_line("--preferSwitch") void bar_generic<T>(T v, out bit<8> y) {
+    switch (v) {
+        0b1: {
+            y = 1;
+        }
+        0b10: {
+            y = 2;
+        }
+        default: {
+            y = 0;
+        }
+    }
+}
+control C(out bit<8> y) {
+    action foo() {
+        bar_generic<bit<2>>(1, y);
+    }
+    table t {
+        actions = {
+            foo;
+        }
+        default_action = foo;
+    }
+    apply {
+        t.apply();
+    }
+}
+
+control proto(out bit<8> y);
+package top(proto p);
+top(C()) main;

testdata/p4_16_errors_outputs/issue5313_type_variable.p4-stderr

@@ -0,0 +1,3 @@
+issue5313_type_variable.p4(6): [--Werror=type-error] error: v: switch expression cannot be of type T
+    switch (v) {
+            ^

testdata/p4_16_errors_outputs/issue5313_typealiass.p4

@@ -0,0 +1,33 @@
+@command_line("--preferSwitch") type bit<2> TwoBitsAlias;
+void bar(bit<2> x, out bit<8> y) {
+    TwoBitsAlias a = (TwoBitsAlias)x;
+    switch (a) {
+        0b1: {
+            y = 4;
+        }
+        0b10: {
+            y = 5;
+        }
+        default: {
+            y = y;
+        }
+    }
+}
+control C(out bit<8> y) {
+    action foo() {
+        bar(1, y);
+    }
+    table t {
+        actions = {
+            foo;
+        }
+        default_action = foo;
+    }
+    apply {
+        t.apply();
+    }
+}
+
+control proto(out bit<8> y);
+package top(proto p);
+top(C()) main;

testdata/p4_16_errors_outputs/issue5313_typealiass.p4-stderr

@@ -0,0 +1,3 @@
+issue5313_typealiass.p4(7): [--Werror=type-error] error: a: switch expression cannot be of type TwoBitsAlias
+    switch (a) {
+            ^

testdata/p4_16_errors_outputs/stmt-switch-on-unsupported-type.p4-stderr

@@ -1,6 +1,6 @@
 stmt-switch-on-unsupported-type.p4(3): [--Wwarn=unused] warning: control 'ctrl' is unused
 control ctrl()() {
         ^^^^
-stmt-switch-on-unsupported-type.p4(5): [--Werror=type-error] error: ...: could not find default value
+stmt-switch-on-unsupported-type.p4(5): [--Werror=type-error] error: ...: switch expression cannot be of type ANYTYPE
     switch (...) { }
             ^^^

testdata/p4_16_samples/issue5313.p4

@@ -0,0 +1,28 @@
+@command_line("--preferSwitch")
+
+void bar(bit<2> x, out bit<8> y) {
+    switch (x) {
+        0b01: { y = 2; }
+        0b10: { y = 3; }
+    }
+}
+
+control C(out bit<8> y) {
+    action foo() {
+        bar(1, y);
+    }
+
+    table t {
+        actions = { foo; }
+        default_action = foo;
+    }
+
+    apply {
+        t.apply();
+    }
+}
+
+control proto(out bit<8> y);
+package top(proto p);
+
+top(C()) main;

testdata/p4_16_samples/issue5313_aliass.p4

@@ -0,0 +1,30 @@
+@command_line("--preferSwitch")
+
+typedef bit<2> TwoBits;
+
+void bar(TwoBits x, out bit<8> y) {
+    switch (x) {
+        0b01: { y = 2; }
+        0b10: { y = 3; }
+    }
+}
+
+control C(out bit<8> y) {
+    action foo() {
+        bar(1, y);
+    }
+
+    table t {
+        actions = { foo; }
+        default_action = foo;
+    }
+
+    apply {
+        t.apply();
+    }
+}
+
+control proto(out bit<8> y);
+package top(proto p);
+
+top(C()) main;

testdata/p4_16_samples_outputs/issue5313-first.p4

@@ -0,0 +1,28 @@
+@command_line("--preferSwitch") void bar(bit<2> x, out bit<8> y) {
+    switch (x) {
+        2w0b1: {
+            y = 8w2;
+        }
+        2w0b10: {
+            y = 8w3;
+        }
+    }
+}
+control C(out bit<8> y) {
+    action foo() {
+        bar(2w1, y);
+    }
+    table t {
+        actions = {
+            foo();
+        }
+        default_action = foo();
+    }
+    apply {
+        t.apply();
+    }
+}
+
+control proto(out bit<8> y);
+package top(proto p);
+top(C()) main;

testdata/p4_16_samples_outputs/issue5313-frontend.p4

@@ -0,0 +1,27 @@
+control C(out bit<8> y) {
+    @name("C.y_0") bit<8> y_1;
+    @name("C.foo") action foo() {
+        switch (2w1) {
+            2w0b1: {
+                y_1 = 8w2;
+            }
+            2w0b10: {
+                y_1 = 8w3;
+            }
+        }
+        y = y_1;
+    }
+    @name("C.t") table t_0 {
+        actions = {
+            foo();
+        }
+        default_action = foo();
+    }
+    apply {
+        t_0.apply();
+    }
+}
+
+control proto(out bit<8> y);
+package top(proto p);
+top(C()) main;

testdata/p4_16_samples_outputs/issue5313-midend.p4

@@ -0,0 +1,27 @@
+control C(out bit<8> y) {
+    @name("C.y_0") bit<8> y_1;
+    @name("C.foo") action foo() {
+        switch (2w1) {
+            2w0b1: {
+                y_1 = 8w2;
+            }
+            2w0b10: {
+                y_1 = 8w3;
+            }
+        }
+        y = y_1;
+    }
+    @name("C.t") table t_0 {
+        actions = {
+            foo();
+        }
+        default_action = foo();
+    }
+    apply {
+        t_0.apply();
+    }
+}
+
+control proto(out bit<8> y);
+package top(proto p);
+top(C()) main;