diff options
Diffstat (limited to 'source')
| -rw-r--r-- | source/slang/core.meta.slang | 19 | ||||
| -rw-r--r-- | source/slang/slang-lower-to-ir.cpp | 39 |
2 files changed, 52 insertions, 6 deletions
diff --git a/source/slang/core.meta.slang b/source/slang/core.meta.slang index 0c39f2c2f..b56ca3085 100644 --- a/source/slang/core.meta.slang +++ b/source/slang/core.meta.slang @@ -192,7 +192,9 @@ ${{{{ // Declare initializers to convert from various other types for (int ss = 0; ss < kBaseTypeCount; ++ss) { - // Don't allow conversion from `void` + // Don't allow conversion to or from `void` + if (kBaseTypes[tt].tag == BaseType::Void) + continue; if (kBaseTypes[ss].tag == BaseType::Void) continue; @@ -250,6 +252,21 @@ ${{{{ ${{{{ break; } + + // If this is the `void` type, then we want to allow + // explicit conversion to it from any other type, using + // `(void) someExpression`. + // + if( kBaseTypes[tt].tag == BaseType::Void ) + { +}}}} + __generic<T> + [__readNone] + __init(T value) + {} +${{{{ + } + }}}} } diff --git a/source/slang/slang-lower-to-ir.cpp b/source/slang/slang-lower-to-ir.cpp index 42f53ef22..fa23b3307 100644 --- a/source/slang/slang-lower-to-ir.cpp +++ b/source/slang/slang-lower-to-ir.cpp @@ -3610,18 +3610,47 @@ struct StmtLoweringVisitor : StmtVisitor<StmtLoweringVisitor> { startBlockIfNeeded(stmt); - // A `return` statement turns into a return - // instruction. If the statement had an argument - // expression, then we need to lower that to - // a value first, and then emit the resulting value. + // A `return` statement turns into a `return` instruction, + // but we have two kinds of `return`: one for returning + // a (non-`void`) value, and one for returning "no value" + // (which effectively returns a value of type `void`). + // if( auto expr = stmt->expression ) { + // If the AST `return` statement had an expression, then we + // need to lower it to the IR at this point, both to + // compute its value and (in case we are returning a + // `void`-typed expression) to execute its side effects. + // auto loweredExpr = lowerRValueExpr(context, expr); - getBuilder()->emitReturn(getSimpleVal(context, loweredExpr)); + // If the AST `return` statement was returning a non-`void` + // value, then we need to emit an IR `return` of that value. + // + if(!expr->type.type->equals(context->astBuilder->getVoidType())) + { + getBuilder()->emitReturn(getSimpleVal(context, loweredExpr)); + } + else + { + // If the type of the value returned was `void`, then + // we don't want to emit an IR-level `return` with a value, + // because that could trip up some of our back-end. + // + // TODO: We should eventually have only a single IR-level + // `return` operation that always takes a value (including + // values of type `void`), and then treat an AST `return;` + // as equivalent to something like `return void();`. + // + getBuilder()->emitReturn(); + } } else { + // If we hit this case, then the AST `return` was a `return;` + // with no value, which can only occur in a function with + // a `void` result type. + // getBuilder()->emitReturn(); } } |
