Disallow switch statements in runtime effects

Bug: skia:10680
Change-Id: Ic77f7355866363ef476a93d8da180cf53207fa6d
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/353707
Commit-Queue: Brian Osman <brianosman@google.com>
Reviewed-by: John Stiles <johnstiles@google.com>

src/sksl/SkSLIRGenerator.cpp

@@ -634,6 +634,11 @@ std::unique_ptr<Statement> IRGenerator::convertDo(const ASTNode& d) {
 
 std::unique_ptr<Statement> IRGenerator::convertSwitch(const ASTNode& s) {
     SkASSERT(s.fKind == ASTNode::Kind::kSwitch);
+    if (this->strictES2Mode()) {
+        this->errorReporter().error(s.fOffset, "switch statements are not supported");
+        return nullptr;
+    }
+
     AutoSwitchLevel level(this);
     auto iter = s.begin();
     std::unique_ptr<Expression> value = this->convertExpression(*(iter++));

tests/sksl/runtime_errors/IllegalStatements.rte

@@ -1,7 +1,9 @@
-// Expect 3 errors
+// Expect 4 errors
 
 void discard_stmt() { discard; }
 
 int do_loop(int x) { do { x++; } while(x < 1); return x; }
 
 int while_loop(int x) { while (x < 1) { x++; } return x; }
+
+int switch_stmt(int x) { switch (x) { case 0: return 1; default: return x; } }

tests/sksl/runtime_errors/golden/IllegalStatements.skvm

@@ -3,4 +3,5 @@
 error: 3: discard statement is only permitted in fragment shaders
 error: 5: do-while loops are not supported
 error: 7: while loops are not supported
-3 errors
+error: 9: switch statements are not supported
+4 errors