Split out target code generation from CLikeSourceEmitter (#976)

* * Added SourceStyle to CLikeSourceEmitter, to limit cases to actual target types.
* Made Impl methods _ prefixed
* Small tidyup

* * SourceStream -> SourceWriter
* use slang-emit- prefix on SourceWriter file

* * Remove EmitContext -> merge into CLikeSourceEmitter

* slang-c-like-source-emitter -> slang-emit-source.cpp

* ExtensionUsageTracker -> GLSLExtensionTracker
slang-extension-usage-tracker.cpp/.h -> slang-emit-glsl-extension-tracker.cpp/.h

* emit-source.cpp.h -> emit-c-like.cpp/.h

* Small fix to move where some _ prefixed functions are declared in CLikeSourceEmitter.

* * CLikeSourceEmitter::CInfo -> Desc
* Functions to get and find CodeGenTarget by name
* Split out empty language impls
* Create an impl based on SourceStyle

* * CodeGenTarget conversion to and from string

* Move HLSL specific functions to HLSLEmitSource.

* Emitting texture and image types.

* Move move GLSL specific functionality to GLSLSourceEmitter

* Split more out of slang-emit-c-like

* Refactor more out of slang-emit-c-like

* * tryEmitIRInstExprImpl(IRInst* inst, IREmitMode mode, const EmitOpInfo& inOuterPrec)
* Fix bug around output of uintBitsToFloat

* More work refactoring out target specifics from slang-emit-c-like

* Move functions that are only implemented once in GLSL impl into their Impl method.

* Move rate qualification out of slang-emit-c-like

* * Added getEmitOpForOp - allows for table usage so different ops can be dealt with the same way
* Moved vector comparison to slang-emit-glsl
*

* * Use EmitOpInfo to control output in slang-emit-c-like.cpp for unary ops

* Move more functionality from CLikeSourceEmitter to HLSLSourceEmitter

* Make output of parameters implementaion specific.

* Extracted interpolation modifiers.

* Remove IR from methods that don't need them.

* Remove IR from method names.

* Refactor handling of output of types - to make the impls implement the full path without lots of cases for specific impls

* Add variable declaration modifiers and matrix layout to larget specific in slang-emit.

* Make target specific internal functions _ prefixed.

1 files changed, 49 insertions, 17 deletions

diff --git a/source/slang/slang-emit.cpp b/source/slang/slang-emit.cpp
index 3cacb2d90..623c57f2b 100644
--- a/source/slang/slang-emit.cpp
+++ b/source/slang/slang-emit.cpp
@@ -27,6 +27,10 @@
 
 #include "slang-emit-c-like.h"
 
+#include "slang-emit-glsl.h"
+#include "slang-emit-hlsl.h"
+#include "slang-emit-cpp.h"
+
 #include <assert.h>
 
 namespace Slang {
@@ -173,30 +177,58 @@ String emitEntryPoint(
 
     SourceWriter sourceWriter(compileRequest->getSourceManager(), lineDirectiveMode );
 
-    CLikeSourceEmitter::CInfo cinfo;
+    CLikeSourceEmitter::Desc desc;
 
-    cinfo.compileRequest = compileRequest;
-    cinfo.target = target;
-    cinfo.entryPoint = entryPoint;
-    cinfo.effectiveProfile = getEffectiveProfile(entryPoint, targetRequest);
-    cinfo.sourceWriter = &sourceWriter;
+    desc.compileRequest = compileRequest;
+    desc.target = target;
+    desc.entryPoint = entryPoint;
+    desc.effectiveProfile = getEffectiveProfile(entryPoint, targetRequest);
+    desc.sourceWriter = &sourceWriter;
 
     if (entryPoint && programLayout)
     {
-        cinfo.entryPointLayout = findEntryPointLayout(programLayout, entryPoint);
+        desc.entryPointLayout = findEntryPointLayout(programLayout, entryPoint);
     }
 
-    cinfo.programLayout = programLayout;
+    desc.programLayout = programLayout;
 
     // Layout information for the global scope is either an ordinary
     // `struct` in the common case, or a constant buffer in the case
     // where there were global-scope uniforms.
     
     StructTypeLayout* globalStructLayout = programLayout ? getGlobalStructLayout(programLayout) : nullptr;
-    cinfo.globalStructLayout = globalStructLayout;
+    desc.globalStructLayout = globalStructLayout;
+
+    RefPtr<CLikeSourceEmitter> sourceEmitter;
 
-    CLikeSourceEmitter sourceEmitter(cinfo);
+    typedef CLikeSourceEmitter::SourceStyle SourceStyle;
+
+    SourceStyle sourceStyle = CLikeSourceEmitter::getSourceStyle(target);
+    switch (sourceStyle)
+    {
+        case SourceStyle::CPP:
+        {
+            sourceEmitter = new CPPSourceEmitter(desc);
+            break;
+        }
+        case SourceStyle::GLSL:
+        {
+            sourceEmitter = new GLSLSourceEmitter(desc);
+            break;
+        }
+        case SourceStyle::HLSL:
+        {
+            sourceEmitter = new HLSLSourceEmitter(desc);
+            break;
+        }
+        default: break;
+    }
 
+    if (!sourceEmitter)
+    {
+        sink->diagnose(SourceLoc(), Diagnostics::unableToGenerateCodeForTarget, getCodeGenTargetName(target));
+        return String();
+    }
     {
         auto session = targetRequest->getSession();
 
@@ -421,7 +453,7 @@ String emitEntryPoint(
                 irModule,
                 irEntryPoint,
                 compileRequest->getSink(),
-                sourceEmitter.getGLSLExtensionTracker());
+                sourceEmitter->getGLSLExtensionTracker());
 
 #if 0
                 dumpIRIfEnabled(compileRequest, irModule, "GLSL LEGALIZED");
@@ -456,7 +488,7 @@ String emitEntryPoint(
         //
         // TODO: do we want to emit directly from IR, or translate the
         // IR back into AST for emission?
-        sourceEmitter.emitIRModule(irModule);
+        sourceEmitter->emitModule(irModule);
     }
 
     // Deal with cases where a particular stage requires certain GLSL versions
@@ -474,8 +506,8 @@ String emitEntryPoint(
     case Stage::RayGeneration:
         if( target == CodeGenTarget::GLSL )
         {
-            sourceEmitter.getGLSLExtensionTracker()->requireExtension("GL_NV_ray_tracing");
-            sourceEmitter.getGLSLExtensionTracker()->requireVersion(ProfileVersion::GLSL_460);
+            sourceEmitter->getGLSLExtensionTracker()->requireExtension("GL_NV_ray_tracing");
+            sourceEmitter->getGLSLExtensionTracker()->requireVersion(ProfileVersion::GLSL_460);
         }
         break;
     }
@@ -487,16 +519,16 @@ String emitEntryPoint(
     // it is time to stitch together the final output.
 
     // There may be global-scope modifiers that we should emit now
-    sourceEmitter.emitGLSLPreprocessorDirectives();
+    sourceEmitter->emitPreprocessorDirectives();
 
-    sourceEmitter.emitLayoutDirectives(targetRequest);
+    sourceEmitter->emitLayoutDirectives(targetRequest);
 
     String prefix = sourceWriter.getContent();
     
     StringBuilder finalResultBuilder;
     finalResultBuilder << prefix;
 
-    finalResultBuilder << sourceEmitter.getGLSLExtensionTracker()->getExtensionRequireLines();
+    finalResultBuilder << sourceEmitter->getGLSLExtensionTracker()->getExtensionRequireLines();
 
     finalResultBuilder << code;