Fix broken -emit-spirv-via-glsl test option (#7091)

Fixes issue #6898

The -emit-spirv-via-glsl slang-test option has been broken for
some amount of time. Tests that were using it were operating as
if using -emit-spirv-directly, leading to many duplicated tests.

After fixing the test option, there were an number of errors that
appeared as a result.

This change fixes the broken test option and the resulting test
errors. Some of the test errors revealed some legitimate issues,
such as:

-The GLSL bitCount instrinsic only supports 32-bit integers and
 requires emulation for other bit widths.
-Emitting GLSL 8-bit and 16-bit glsl integer types did not emit
 the proper extension requirements
-Emitting GLSL and casting for 16-bit integers was missing a
 closing parenthesis.
-Missing profile for GL_EXT_shader_explicit_arithmetic_types
-Missing toType cases for UInt8/Int8 for the kIROp_BitCast case
 in tryEmitInstExprImpl.

1 files changed, 16 insertions, 0 deletions

diff --git a/tools/render-test/slang-support.cpp b/tools/render-test/slang-support.cpp
index 2f39ed078..f98372330 100644
--- a/tools/render-test/slang-support.cpp
+++ b/tools/render-test/slang-support.cpp
@@ -194,6 +194,22 @@ static SlangResult _compileProgramImpl(
     else
         sessionTargetDesc.flags = 0;
 
+    {
+        slang::CompilerOptionEntry entry;
+        entry.value.kind = slang::CompilerOptionValueKind::Int;
+        if (options.generateSPIRVDirectly)
+        {
+            entry.name = slang::CompilerOptionName::EmitSpirvDirectly;
+            entry.value.intValue0 = int(options.generateSPIRVDirectly);
+        }
+        else
+        {
+            entry.name = slang::CompilerOptionName::EmitSpirvViaGLSL;
+            entry.value.intValue0 = int(!options.generateSPIRVDirectly);
+        }
+        sessionOptionEntries.add(entry);
+    }
+
     // Not expecting argument parsing to have added any targets
     SLANG_ASSERT(sessionDesc.targetCount == 0);
     sessionDesc.targetCount = 1;