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, 14 insertions, 0 deletions

diff --git a/source/compiler-core/slang-downstream-compiler.h b/source/compiler-core/slang-downstream-compiler.h
index c96003cc4..5365b9839 100644
--- a/source/compiler-core/slang-downstream-compiler.h
+++ b/source/compiler-core/slang-downstream-compiler.h
@@ -340,6 +340,9 @@ public:
     /// Disassemble and print to stdout
     virtual SLANG_NO_THROW SlangResult SLANG_MCALL
     disassemble(const uint32_t* contents, int contentsSize) = 0;
+    /// Disassemble and return the result as a string
+    virtual SLANG_NO_THROW SlangResult SLANG_MCALL
+    disassembleWithResult(const uint32_t* contents, int contentsSize, String& outString) = 0;
 
     /// True if underlying compiler uses file system to communicate source
     virtual SLANG_NO_THROW bool SLANG_MCALL isFileBased() = 0;
@@ -398,6 +401,17 @@ public:
         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;
+    }
+
     DownstreamCompilerBase(const Desc& desc)
         : m_desc(desc)
     {