Implement notion of a "container format" (#213)

The big addition here is that the Slang "bytecode" is no longer treated as just a "code generation target" (`CodeGenTarget`) akin to DX bytecode (DXBC) or SPIR-V, but instead is a `ContainerFormat` that can be used to emit all the results of a compile request (well, currently just the IR-as-BC, but the intention is there).

Getting to this goal involved some prior checkins that eliminated bogus "targets" that weren't really akin to SPIR-V or DXBC: `-target slang-ir-asm` and `-target reflection-json`. Those targets were really in place to support testing, and so they've been made more explicit testing/debug options.

This change eliminates `-target slang-ir` and instead tries to allow the user to specify `-o foo.slang-module` as an output file name, that indicates the intention to output a "container" file that will wrap up all the generated code.

I've also gone ahead and generalized the existing `-target` option so that we are actually building up a *list* of code generation targets. This is largely just a cleanup, since it forces code to be more aware of when it is doing something target-specific vs. target independent. For example, reflection layout information lives on a requested target, and not on the compile request as a whole, and similarly output code is per-target, per-entry-point.

As a cleanup, I eliminated support for per-translation-unit output. This was vestigial code from back when I used to try and do HLSL generation for a whole translation unit instead of per-entry-point (which turned out to be a lot of complexity for little gain), and it was only being used in the `hello` example and the `render-test` test fixture - in both cases fixing it up was easy enough. I've stubbed out the old `spGetTranslationUnitSource` API, but haven't removed it yet.

1 files changed, 5 insertions, 15 deletions

diff --git a/source/slang/ir.h b/source/slang/ir.h
index 4fd165c33..ecc77dbc4 100644
--- a/source/slang/ir.h
+++ b/source/slang/ir.h
@@ -97,10 +97,7 @@ enum IRDecorationOp : uint16_t
 {
     kIRDecorationOp_HighLevelDecl,
     kIRDecorationOp_Layout,
-    kIRDecorationOp_EntryPoint,
-    kIRDecorationOp_ComputeThreadGroupSize,
     kIRDecorationOp_LoopControl,
-    kIRDecorationOp_MangledName,
 };
 
 // A "decoration" that gets applied to an instruction.
@@ -291,6 +288,11 @@ struct IRGlobalValue : IRValue
 {
     IRModule*   parentModule;
 
+    // The mangled name, for a symbol that should have linkage,
+    // or which might have multiple declarations.
+    String mangledName;
+
+
     IRGlobalValue*  nextGlobalValue;
     IRGlobalValue*  prevGlobalValue;
 
@@ -319,10 +321,6 @@ struct IRFunc : IRGlobalValue
     // The type of the IR-level function
     IRFuncType* getType() { return (IRFuncType*) type.Ptr(); }
 
-    // The mangled name, for a function
-    // that should have linkage.
-    String mangledName;
-
     // Any generic parameters this function has
     List<RefPtr<Decl>> genericParams;
 
@@ -367,14 +365,6 @@ void printSlangIRAssembly(StringBuilder& builder, IRModule* module);
 String getSlangIRAssembly(IRModule* module);
 
 void dumpIR(IRModule* module);
-
-// IR transformations
-
-// Transform shader entry points so that they conform to GLSL rules.
-void legalizeEntryPointsForGLSL(
-        Session*    session,
-        IRModule*   module);
-
 }