Precompiled SPIR-V import support (#5048)

* Precompiled SPIR-V import support

Adds appropriate linkage and function declaration syntax
for SPIR-V functions that are declared, to be imported
from another SPIR-V module.

Unlike DXIL, stripping the Slang IR for a function down
to a declaration requires retaining a block of parameters,
as the function declaration must be emitted to SPIR-V
with the same parameters as a definition. Because that
thwarts the logic in Slang to tell the difference between
a declaration and definition, and explicit decoration is
introduced to explicitly mark functions which need to be
treated as declarations during emit phase.

Fixes #4992

Co-authored-by: Yong He <yonghe@outlook.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/tests/library/precompiled-spirv-generics.slang b/tests/library/precompiled-spirv-generics.slang
index a55f58513..64fd8a64c 100644
--- a/tests/library/precompiled-spirv-generics.slang
+++ b/tests/library/precompiled-spirv-generics.slang
@@ -24,5 +24,5 @@ struct Attributes
 [shader("anyhit")]
 void anyhit(inout Payload payload, Attributes attrib)
 {
-    payload.val = normalFunc(x * y) + normalFuncUsesGeneric(y);
+    payload.val = normalFunc(floor(x * y), x) + normalFuncUsesGeneric(y);
 }