Fix up emission of shader parameter semantics when using IR (#226)

* Fix up emission of shader parameter semantics when using IR

- Make sure to propagate entry point parameter layouts down to IR parameters when doing the initial cloning to form target-specific IR

- When layout information is present on an IR node, prefer to use that over the original high-level declaration for outputting semantics in final HLSL

- Fix up test runner to generate `.actual` files when running compute tests, in cases where the `render-test` application errors out (e.g., because of a Slang compilation error)

- Add a first test of generics functionality, to show that they generate valid code through the IR
  - Right now this test is *not* using any "interesting" operations on the type parameter, so this is not a test that can confirm that interface constraints work

* fixup: skip compute tests when running on Linux

1 files changed, 25 insertions, 0 deletions

diff --git a/source/slang/ir.cpp b/source/slang/ir.cpp
index 5ace50397..4c01e4fc1 100644
--- a/source/slang/ir.cpp
+++ b/source/slang/ir.cpp
@@ -3094,6 +3094,31 @@ namespace Slang
             clonedFunc,
             entryPointLayout);
 
+        // We will also go on and attach layout information
+        // to the function parameters, so that we have it
+        // available directly on the parameters, rather
+        // than having to look it up on the original entry-point layout.
+        if( auto firstBlock = clonedFunc->getFirstBlock() )
+        {
+            UInt paramLayoutCount = entryPointLayout->fields.Count();
+            UInt paramCounter = 0;
+            for( auto pp = firstBlock->getFirstParam(); pp; pp = pp->getNextParam() )
+            {
+                UInt paramIndex = paramCounter++;
+                if( paramIndex < paramLayoutCount )
+                {
+                    auto paramLayout = entryPointLayout->fields[paramIndex];
+                    context->builder->addLayoutDecoration(
+                        pp,
+                        paramLayout);
+                }
+                else
+                {
+                    SLANG_UNEXPECTED("too many parameters");
+                }
+            }
+        }
+
         return clonedFunc;
     }