Cleanups on slang-generate (#437)

* Cleanups on slang-generate

There is nothing too significant in these changes, but I'm trying to get
things in place so that we can:

- Clean up the stdlib code to do less explicit `StringBuilder`
operations and instead to use more of the "template engine" approach

- Start using slang-generate for code other than the slang stdlib, so
that we can generate more of our boilerplate.

The main new functionality here is that in a template/meta file, you can
now enclose an expression in `$(...)` to indicate that is should be
spliced into the result. E.g. instead of:

    class ${{ sb << someClassName; }}
    {
        ...
    }

We can now write:

    class $(someClassName)
    {
        ...
    }

The other bit of new functionality is support for a whole-line statement
escape, so that instead of:

    ${{ for( auto a : someCollection ) { }}
    void $(a)() { ... }
    ${{ } }}

We can instead write:

    $: for(auto a : someCollection) {
    void $(a)() { ... }
    $: }

I haven't yet tried to use that functionality in the stdlib meta-code,
but doing so would be an obvious next step.

* Fixup: change some $P to $p

The capitalization on some of the GLSL intrinsic mappings got messed up during a find-and-replace operation when removing the double `$` that used to be required to escape things.

1 files changed, 6 insertions, 14 deletions

diff --git a/source/slang/hlsl.meta.slang b/source/slang/hlsl.meta.slang
index 03b48e805..15579e512 100644
--- a/source/slang/hlsl.meta.slang
+++ b/source/slang/hlsl.meta.slang
@@ -31,10 +31,7 @@ __magic_type(HLSLByteAddressBufferType) struct ByteAddressBuffer
 
 __generic<T>
 __magic_type(HLSLStructuredBufferType)
-__intrinsic_type(${{
-	// TODO: we really need a simple way to write an "expression splice"
-	sb << kIROp_structuredBufferType;
-}})
+__intrinsic_type($(kIROp_structuredBufferType))
 struct StructuredBuffer
 {
     void GetDimensions(
@@ -181,10 +178,7 @@ __magic_type(HLSLRWByteAddressBufferType) struct RWByteAddressBuffer
 
 __generic<T>
 __magic_type(HLSLRWStructuredBufferType)
-__intrinsic_type(${{
-	// TODO: we really need a simple way to write an "expression splice"
-	sb << kIROp_readWriteStructuredBufferType;
-}})
+__intrinsic_type($(kIROp_readWriteStructuredBufferType))
 struct RWStructuredBuffer
 {
     uint DecrementCounter();
@@ -265,7 +259,7 @@ __target_intrinsic(glsl, "bool($0)")
 bool any(T x);
 
 __generic<T : __BuiltinType, let N : int>
-__target_intrinsic(glsl, "any(bvec$$N0($0))")
+__target_intrinsic(glsl, "any(bvec$N0($0))")
 bool any(vector<T,N> x);
 
 __generic<T : __BuiltinType, let N : int, let M : int>
@@ -1053,7 +1047,6 @@ __generic<T : __BuiltinType, let N : int, let M : int> matrix<T,N,M> WaveReadLan
 typedef Texture2D texture2D;
 
 ${{{{
-
 // Component-wise multiplication ops
 for(auto op : binaryOps)
 {
@@ -1109,14 +1102,14 @@ for (int aa = 0; aa < kBaseBufferAccessLevelCount; ++aa)
 
     sb << "void GetDimensions(out uint dim);\n";
 
-    sb << "__target_intrinsic(glsl, \"texelFetch($$P, $1)$$z\")\n";
+    sb << "__target_intrinsic(glsl, \"texelFetch($P, $1)$z\")\n";
     sb << "T Load(int location);\n";
 
     sb << "T Load(int location, out uint status);\n";
 
     sb << "__subscript(uint index) -> T {\n";
 
-    sb << "__target_intrinsic(glsl, \"texelFetch($$P, int($1))$$z\") get;\n";
+    sb << "__target_intrinsic(glsl, \"texelFetch($P, int($1))$z\") get;\n";
 
     if (kBaseBufferAccessLevels[aa].access != SLANG_RESOURCE_ACCESS_READ)
     {
@@ -1127,5 +1120,4 @@ for (int aa = 0; aa < kBaseBufferAccessLevelCount; ++aa)
 
     sb << "};\n";
 }
-
-}}}}
\ No newline at end of file
+}}}}