IR: Add SPIR-V disassembly for embedded downstream IR dumps (#6529)

* IR: Add SPIR-V disassembly for embedded downstream IR dumps

When dumping IR that contains embedded downstream SPIR-V code (via
EmbeddedDownstreamIR instructions), display the disassembled SPIR-V
instead of just showing "<binary blob>".

This CL also does:
- Adds a new interface for disassembly and get result.
- Modify export-library-generics.slang test test to check for the
  disassembled SPIR-V

Fixes #6513

* Add module-dual-target-verify test

Fixes #6517
Adds a new test to verify that dxil and spirv targets are stored
separately in the precompiled blob.

* Fix review comments from cheneym2

* format code

---------

Co-authored-by: slangbot <186143334+slangbot@users.noreply.github.com>

1 files changed, 10 insertions, 1 deletions

diff --git a/source/slang-llvm/slang-llvm.cpp b/source/slang-llvm/slang-llvm.cpp
index 86565a485..e645fb3c7 100644
--- a/source/slang-llvm/slang-llvm.cpp
+++ b/source/slang-llvm/slang-llvm.cpp
@@ -1,4 +1,3 @@
-
 #include "clang/Basic/Stack.h"
 #include "clang/Basic/TargetOptions.h"
 #include "clang/Basic/Version.h"
@@ -147,6 +146,16 @@ public:
         SLANG_UNUSED(contentsSize);
         return SLANG_FAIL;
     }
+    virtual SLANG_NO_THROW SlangResult SLANG_MCALL disassembleWithResult(
+        const uint32_t* contents,
+        int contentsSize,
+        String& outString) SLANG_OVERRIDE
+    {
+        SLANG_UNUSED(contents);
+        SLANG_UNUSED(contentsSize);
+        SLANG_UNUSED(outString);
+        return SLANG_FAIL;
+    }
 
     LLVMDownstreamCompiler()
         : m_desc(