Improve support for non-32-bit types. (#643)

The main change here is to fill out the `BaseType` enumeration so that it covers the full range of 8/16/32/64-bit signed and unsigned integers, as well as 16/32/64-bit floating-point numbers, and then propagate that completion through various places in the code.

More details:

* The current `half`, `float`, `double`, `int`, and `uint` types are still the default names for their types, so things like `float16_t` and `int32_t` were added as `typedef`s.

* We still need to generate the full gamut of vector/matrix `typedef`s for the new types, so that things like `float16_t4x3` will work (yes, I know that is ugly as sin, but that's the HLSL syntax...).

* A few pieces of dead code from earlier in the compiler's life got removed, since I did a find-in-files for `BaseType::` and tried to either update or delete every site.

* A few call sites that were enumerating integer base types in an ad-hoc fashion were changed to use a single `isIntegerBaseType()` function that I added in `check.cpp`

* When compiling with dxc for shader model 6.2 and up, we enable the compiler's support for native 16-bit types via a flag.

* The public API enumeration for reflection of scalar types added cases for 8- and 16-bit integers (it already exposed the other cases we need)

* The lexer was updated to be extremely liberal in what kinds of suffixes it allows on literals. I also removed the logic that was treating, e.g., `0f` as a floating-point literal (it doesn't seem to be the right behavior). That would now be an integer literal with an invalid suffix.

* The logic in the parser that applies types to literals was updated to handle a few more cases: `LL` and `ULL` for 64-bit integers, and `H` for 16-bit floats.

* The mangling logic needed to be updated to handle the new cases, and I consolidated the handling of those types in their front-end and IR forms.

* Removed the explicit `BasicExpressionType::ToString` logic, since all basic types are `DeclRefType`s in the front end, and we can just print them out as such.

* As a bit of a gross hack, fudged the conversion costs so that `int` to `int64_t` conversion is a bit more costly. The problem there is that given an operation like `int(0) + uint(0)`, the best applicable candidates ended up being `+(uint,uint)` and `+(int64_t,int64_t)` because the cost of a single `int`-to-`uint` conversion was the same as the sum of the cost of an `int`-to-`int64_t` and a `uint`-to-`int64_t`. A better long-term fix here is to completely change our overload resolution strategy, but that is obviously way too big to squeeze into this change.

* Type layout computation was updated to handle all the new types and give them their natural size/alignment. Note that this does *not* work for down-level HLSL where `half` is treated as a synonym for `float`. It also doesn't deal with the fact that many of these types aren't actually allowed in constant buffers for certain shader models. A future change should work to add error messages for unsupported stuff during type layout (or just make the types themselves require support for certain capabilities)

1 files changed, 24 insertions, 5 deletions

diff --git a/source/slang/emit.cpp b/source/slang/emit.cpp
index 74678ef94..1e833838c 100644
--- a/source/slang/emit.cpp
+++ b/source/slang/emit.cpp
@@ -786,10 +786,20 @@ struct EmitVisitor
             // no prefix
             break;
 
-        case kIROp_IntType:		Emit("i");		break;
-        case kIROp_UIntType:	Emit("u");		break;
-        case kIROp_BoolType:	Emit("b");		break;
-        case kIROp_DoubleType:	Emit("d");		break;
+        case kIROp_Int8Type:    Emit("i8");     break;
+        case kIROp_Int16Type:   Emit("i16");    break;
+        case kIROp_IntType:     Emit("i");      break;
+        case kIROp_Int64Type:   Emit("i64");    break;
+
+        case kIROp_UInt8Type:   Emit("u8");     break;
+        case kIROp_UInt16Type:  Emit("u16");    break;
+        case kIROp_UIntType:    Emit("u");      break;
+        case kIROp_UInt64Type:  Emit("u64");    break;
+
+        case kIROp_BoolType:    Emit("b");		break;
+
+        case kIROp_HalfType:    Emit("f16");		break;
+        case kIROp_DoubleType:  Emit("d");		break;
 
         case kIROp_VectorType:
             emitGLSLTypePrefix(cast<IRVectorType>(type)->getElementType());
@@ -1179,9 +1189,18 @@ struct EmitVisitor
             break;
 
         case kIROp_VoidType:    Emit("void");       return;
+        case kIROp_BoolType:    Emit("bool");       return;
+
+        case kIROp_Int8Type:    Emit("int8_t");     return;
+        case kIROp_Int16Type:   Emit("int16_t");    return;
         case kIROp_IntType:     Emit("int");        return;
+        case kIROp_Int64Type:   Emit("int64_t");    return;
+
+        case kIROp_UInt8Type:   Emit("uint8_t");    return;
+        case kIROp_UInt16Type:  Emit("uint16_t");   return;
         case kIROp_UIntType:    Emit("uint");       return;
-        case kIROp_BoolType:    Emit("bool");       return;
+        case kIROp_UInt64Type:  Emit("uint64_t");   return;
+
         case kIROp_HalfType:    Emit("half");       return;
         case kIROp_FloatType:   Emit("float");      return;
         case kIROp_DoubleType:  Emit("double");     return;