Introduce an IR-level type system (#481)

* Introduce an IR-level type system

Up to this point, the Slang IR has used the front-end type system to represent types in the IR.
As a result (but ultimately more importantly) the IR representation of generics and specialization has used AST-level concepts embedded in the IR.
For example, to express the specialization of `vector<T,N>` to a concrete type `float` for `T`, we needed an IR operation that could represent the specialization, with operands that somehow represented the type argument `float`.
The whole thing was very complicated.

The big idea of this change is to introduce a new representation in which types in the IR are just ordinary instructions, so that using them as operands makes sense. The hierarchy of IR types closely mirrors the AST-side hierarchy for now, and that will probably be something we should maintain going forward.

In order to make these changes work, though, I also had to do major overhauls of things like the way substitutions are performed, how we check interface conformances, the way lookup through interface types is done, etc. etc. This is a big change, and unfortunately any attempt to summarize it in the commit message wouldn't do it justice.

* Fix 64-bit build warning

* Fix up some clang warnings/errors

1 files changed, 52 insertions, 18 deletions

diff --git a/source/slang/hlsl.meta.slang b/source/slang/hlsl.meta.slang
index 75d9a3d33..977cb54b9 100644
--- a/source/slang/hlsl.meta.slang
+++ b/source/slang/hlsl.meta.slang
@@ -2,7 +2,10 @@
 
 typedef uint UINT;
 
-__generic<T> __magic_type(HLSLAppendStructuredBufferType) struct AppendStructuredBuffer
+__generic<T>
+__magic_type(HLSLAppendStructuredBufferType)
+__intrinsic_type($(kIROp_HLSLAppendStructuredBufferType))
+struct AppendStructuredBuffer
 {
     void Append(T value);
 
@@ -11,7 +14,9 @@ __generic<T> __magic_type(HLSLAppendStructuredBufferType) struct AppendStructure
         out uint stride);
 };
 
-__magic_type(HLSLByteAddressBufferType) struct ByteAddressBuffer
+__magic_type(HLSLByteAddressBufferType)
+__intrinsic_type($(kIROp_HLSLByteAddressBufferType))
+struct ByteAddressBuffer
 {
     void GetDimensions(
         out uint dim);
@@ -31,7 +36,7 @@ __magic_type(HLSLByteAddressBufferType) struct ByteAddressBuffer
 
 __generic<T>
 __magic_type(HLSLStructuredBufferType)
-__intrinsic_type($(kIROp_structuredBufferType))
+__intrinsic_type($(kIROp_HLSLStructuredBufferType))
 struct StructuredBuffer
 {
     void GetDimensions(
@@ -44,7 +49,10 @@ struct StructuredBuffer
     __subscript(uint index) -> T { __intrinsic_op(bufferLoad) get; };
 };
 
-__generic<T> __magic_type(HLSLConsumeStructuredBufferType) struct ConsumeStructuredBuffer
+__generic<T>
+__magic_type(HLSLConsumeStructuredBufferType)
+__intrinsic_type($(kIROp_HLSLConsumeStructuredBufferType))
+struct ConsumeStructuredBuffer
 {
     T Consume();
 
@@ -53,17 +61,25 @@ __generic<T> __magic_type(HLSLConsumeStructuredBufferType) struct ConsumeStructu
         out uint stride);
 };
 
-__generic<T, let N : int> __magic_type(HLSLInputPatchType) struct InputPatch
+__generic<T, let N : int>
+__magic_type(HLSLInputPatchType)
+__intrinsic_type($(kIROp_HLSLInputPatchType))
+struct InputPatch
 {
     __subscript(uint index) -> T;
 };
 
-__generic<T, let N : int> __magic_type(HLSLOutputPatchType) struct OutputPatch
+__generic<T, let N : int>
+__magic_type(HLSLOutputPatchType)
+__intrinsic_type($(kIROp_HLSLOutputPatchType))
+struct OutputPatch
 {
     __subscript(uint index) -> T;
 };
 
-__magic_type(HLSLRWByteAddressBufferType) struct RWByteAddressBuffer
+__magic_type(HLSLRWByteAddressBufferType)
+__intrinsic_type($(kIROp_HLSLRWByteAddressBufferType))
+struct RWByteAddressBuffer
 {
     // Note(tfoley): supports alll operations from `ByteAddressBuffer`
     // TODO(tfoley): can this be made a sub-type?
@@ -178,7 +194,7 @@ __magic_type(HLSLRWByteAddressBufferType) struct RWByteAddressBuffer
 
 __generic<T>
 __magic_type(HLSLRWStructuredBufferType)
-__intrinsic_type($(kIROp_readWriteStructuredBufferType))
+__intrinsic_type($(kIROp_HLSLRWStructuredBufferType))
 struct RWStructuredBuffer
 {
     uint DecrementCounter();
@@ -199,7 +215,10 @@ struct RWStructuredBuffer
 	}
 };
 
-__generic<T> __magic_type(HLSLPointStreamType) struct PointStream
+__generic<T>
+__magic_type(HLSLPointStreamType)
+__intrinsic_type($(kIROp_HLSLPointStreamType))
+struct PointStream
 {
     __target_intrinsic(glsl, "EmitVertex()")
     void Append(T value);
@@ -208,7 +227,10 @@ __generic<T> __magic_type(HLSLPointStreamType) struct PointStream
     void RestartStrip();
 };
 
-__generic<T> __magic_type(HLSLLineStreamType) struct LineStream
+__generic<T>
+__magic_type(HLSLLineStreamType)
+__intrinsic_type($(kIROp_HLSLLineStreamType))
+struct LineStream
 {
     __target_intrinsic(glsl, "EmitVertex()")
     void Append(T value);
@@ -217,7 +239,10 @@ __generic<T> __magic_type(HLSLLineStreamType) struct LineStream
     void RestartStrip();
 };
 
-__generic<T> __magic_type(HLSLTriangleStreamType) struct TriangleStream
+__generic<T>
+__magic_type(HLSLTriangleStreamType)
+__intrinsic_type($(kIROp_HLSLTriangleStreamType))
+struct TriangleStream
 {
     __target_intrinsic(glsl, "EmitVertex()")
     void Append(T value);
@@ -1098,10 +1123,11 @@ static const int kBaseBufferAccessLevelCount = sizeof(kBaseBufferAccessLevels) /
 
 for (int aa = 0; aa < kBaseBufferAccessLevelCount; ++aa)
 {
-
-    sb << "__generic<T> __magic_type(Texture, ";
-    sb << TextureFlavor::create(TextureFlavor::Shape::ShapeBuffer, kBaseBufferAccessLevels[aa].access).flavor;
-    sb << ") struct ";
+    auto flavor = TextureFlavor::create(TextureFlavor::Shape::ShapeBuffer, kBaseBufferAccessLevels[aa].access).flavor;
+    sb << "__generic<T>\n";
+    sb << "__magic_type(Texture," << int(flavor) << ")\n";
+    sb << "__intrinsic_type(" << (kIROp_FirstTextureType + flavor) << ")\n";
+    sb << "struct ";
     sb << kBaseBufferAccessLevels[aa].name;
     sb << "Buffer {\n";
 
@@ -1151,7 +1177,10 @@ static const RAY_FLAG RAY_FLAG_CULL_NON_OPAQUE                  = 0x80;
 
 // 10.1.2 - Ray Description Structure
 
-__builtin struct RayDesc
+__builtin
+__magic_type(RayDescType)
+__intrinsic_type($(kIROp_RayDescType))
+struct RayDesc
 {
     float3 Origin;
     float  TMin;
@@ -1161,7 +1190,9 @@ __builtin struct RayDesc
 
 // 10.1.3 - Ray Acceleration Structure
 
-__builtin __magic_type(UntypedBufferResourceType)
+__builtin
+__magic_type(RaytracingAccelerationStructureType)
+__intrinsic_type($(kIROp_RaytracingAccelerationStructureType))
 struct RaytracingAccelerationStructure {};
 
 // 10.1.4 - Subobject Definitions
@@ -1173,7 +1204,10 @@ struct RaytracingAccelerationStructure {};
 
 // 10.1.5 - Intersection Attributes Structure
 
-__builtin struct BuiltInTriangleIntersectionAttributes
+__builtin
+__magic_type(BuiltInTriangleIntersectionAttributesType)
+__intrinsic_type($(kIROp_BuiltInTriangleIntersectionAttributesType))
+struct BuiltInTriangleIntersectionAttributes
 {
     float2 barycentrics;
 };