HLSL: add subpass input types and methods
Add support for Subpass Input proposal of issue #1069.
Subpass input types are given as:
layout(input_attachment_index = 1) SubpassInput<float4> subpass_f;
layout(input_attachment_index = 2) SubpassInput<int4> subpass_i;
layout(input_attachment_index = 3) SubpassInput<uint4> subpass_u;
layout(input_attachment_index = 1) SubpassInputMS<float4> subpass_ms_f;
layout(input_attachment_index = 2) SubpassInputMS<int4> subpass_ms_i;
layout(input_attachment_index = 3) SubpassInputMS<uint4> subpass_ms_u;
The input attachment may also be specified using attribute syntax:
[[vk::input_attachment_index(7)]] SubpassInput subpass_2;
The template type may be a shorter-than-vec4 vector, but currently user
structs are not supported. (An unimplemented error will be issued).
The load operations are methods on objects of the above type:
float4 result = subpass_f.SubpassLoad();
int4 result = subpass_i.SubpassLoad();
uint4 result = subpass_u.SubpassLoad();
float4 result = subpass_ms_f.SubpassLoad(samp);
int4 result = subpass_ms_i.SubpassLoad(samp);
uint4 result = subpass_ms_u.SubpassLoad(samp);
Additionally, the AST printer could not print EOpSubpass* nodes. Now it can.
Fixes #1069
diff --git a/hlsl/hlslGrammar.cpp b/hlsl/hlslGrammar.cpp
index 4914f20..88eacd9 100755
--- a/hlsl/hlslGrammar.cpp
+++ b/hlsl/hlslGrammar.cpp
@@ -1088,6 +1088,69 @@
return true;
}
+// subpass input type
+// : SUBPASSINPUT
+// | SUBPASSINPUT VECTOR LEFT_ANGLE template_type RIGHT_ANGLE
+// | SUBPASSINPUTMS
+// | SUBPASSINPUTMS VECTOR LEFT_ANGLE template_type RIGHT_ANGLE
+bool HlslGrammar::acceptSubpassInputType(TType& type)
+{
+ // read subpass type
+ const EHlslTokenClass subpassInputType = peek();
+
+ bool multisample;
+
+ switch (subpassInputType) {
+ case EHTokSubpassInput: multisample = false; break;
+ case EHTokSubpassInputMS: multisample = true; break;
+ default:
+ return false; // not a subpass input declaration
+ }
+
+ advanceToken(); // consume the sampler type keyword
+
+ TType subpassType(EbtFloat, EvqUniform, 4); // default type is float4
+
+ if (acceptTokenClass(EHTokLeftAngle)) {
+ if (! acceptType(subpassType)) {
+ expected("scalar or vector type");
+ return false;
+ }
+
+ const TBasicType basicRetType = subpassType.getBasicType() ;
+
+ switch (basicRetType) {
+ case EbtFloat:
+ case EbtUint:
+ case EbtInt:
+ case EbtStruct:
+ break;
+ default:
+ unimplemented("basic type in subpass input");
+ return false;
+ }
+
+ if (! acceptTokenClass(EHTokRightAngle)) {
+ expected("right angle bracket");
+ return false;
+ }
+ }
+
+ const TBasicType subpassBasicType = subpassType.isStruct() ? (*subpassType.getStruct())[0].type->getBasicType()
+ : subpassType.getBasicType();
+
+ TSampler sampler;
+ sampler.setSubpass(subpassBasicType, multisample);
+
+ // Remember the declared return type. Function returns false on error.
+ if (!parseContext.setTextureReturnType(sampler, subpassType, token.loc))
+ return false;
+
+ type.shallowCopy(TType(sampler, EvqUniform));
+
+ return true;
+}
+
// sampler_type
// : SAMPLER
// | SAMPLER1D
@@ -1357,6 +1420,11 @@
return acceptSamplerType(type);
break;
+ case EHTokSubpassInput: // fall through
+ case EHTokSubpassInputMS: // ...
+ return acceptSubpassInputType(type);
+ break;
+
case EHTokBuffer: // fall through
case EHTokTexture1d: // ...
case EHTokTexture1darray: // ...