Added AssertDSLObjectsReleased setting

Change-Id: Ia63f892305c2347e55560141880a0b6a124b84f6
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/429196
Commit-Queue: Ethan Nicholas <ethannicholas@google.com>
Reviewed-by: John Stiles <johnstiles@google.com>

src/sksl/SkSLProgramSettings.h

@@ -74,6 +74,8 @@ struct ProgramSettings {
     bool fDSLMarkVarsDeclared = false;
     // If true, the DSL should install a memory pool when possible.
     bool fDSLUseMemoryPool = true;
+    // If true, DSL objects assert that they were used prior to destruction
+    bool fAssertDSLObjectsReleased = true;
     // External functions available for use in runtime effects. These values are registered in the
     // symbol table of the Program, but ownership is *not* transferred. It is up to the caller to
     // keep them alive.

src/sksl/dsl/DSLExpression.cpp

@@ -92,8 +92,9 @@ DSLExpression::~DSLExpression() {
         return;
     }
 #endif
-    SkASSERTF(fExpression == nullptr,
+    SkASSERTF(!fExpression || !DSLWriter::Settings().fAssertDSLObjectsReleased,
-              "Expression destroyed without being incorporated into program");
+              "Expression destroyed without being incorporated into program (see "
+              "ProgramSettings::fAssertDSLObjectsReleased)");
 }
 
 void DSLExpression::swap(DSLExpression& other) {

src/sksl/dsl/DSLFunction.cpp

@@ -25,7 +25,7 @@ void DSLFunction::init(DSLModifiers modifiers, const DSLType& returnType, skstd:
         modifiers.fModifiers.fFlags |= Modifiers::kHasSideEffects_Flag;
     }
 
-    if (DSLWriter::Context().fConfig->fSettings.fForceNoInline) {
+    if (DSLWriter::Settings().fForceNoInline) {
         // Apply the `noinline` modifier to every function. This allows us to test Runtime
         // Effects without any inlining, even when the code is later added to a paint.
         modifiers.fModifiers.fFlags &= ~Modifiers::kInline_Flag;

src/sksl/dsl/DSLStatement.cpp

@@ -64,7 +64,9 @@ DSLStatement::~DSLStatement() {
         return;
     }
 #endif
-    SkASSERTF(!fStatement, "Statement destroyed without being incorporated into program");
+    SkASSERTF(!fStatement || !DSLWriter::Settings().fAssertDSLObjectsReleased,
+              "Statement destroyed without being incorporated into program (see "
+              "ProgramSettings::fAssertDSLObjectsReleased)");
 }
 
 DSLPossibleStatement::DSLPossibleStatement(std::unique_ptr<SkSL::Statement> statement)

src/sksl/dsl/priv/DSLWriter.cpp

@@ -79,7 +79,11 @@ SkSL::IRGenerator& DSLWriter::IRGenerator() {
 }
 
 const SkSL::Context& DSLWriter::Context() {
-    return IRGenerator().fContext;
+    return Compiler().context();
+}
+
+SkSL::ProgramSettings& DSLWriter::Settings() {
+    return Context().fConfig->fSettings;
 }
 
 const std::shared_ptr<SkSL::SymbolTable>& DSLWriter::SymbolTable() {

src/sksl/dsl/priv/DSLWriter.h

@@ -70,6 +70,11 @@ public:
      */
     static const SkSL::Context& Context();
 
+    /**
+     * Returns the Settings used by DSL operations in the current thread.
+     */
+    static SkSL::ProgramSettings& Settings();
+
     /**
      * Returns the collection to which DSL program elements in this thread should be appended.
      */

tests/SkSLDSLTest.cpp

@@ -1986,3 +1986,12 @@ DEF_GPUTEST_FOR_MOCK_CONTEXT(DSLInlining, r, ctxInfo) {
                  "}");
     REPORTER_ASSERT(r, *program->fSource == source);
 }
+
+DEF_GPUTEST_FOR_MOCK_CONTEXT(DSLReleaseUnused, r, ctxInfo) {
+    SkSL::ProgramSettings settings = default_settings();
+    settings.fAssertDSLObjectsReleased = false;
+    AutoDSLContext context(ctxInfo.directContext()->priv().getGpu(), settings);
+    If(Sqrt(1) > 0, Discard());
+    // Ensure that we can safely destroy statements and expressions despite being unused while
+    // settings.fAssertDSLObjectsReleased is disabled.
+}