Add DebugGlobalVariable instructions to SPIR-V output (#7686)

* Add DebugGlobalVariable instructions to SPIR-V output

Implements generation of DebugGlobalVariable instructions for global variables
like Texture2D and SamplerState in SPIR-V debug information output. Adds debug
type support for texture and sampler types using DebugTypeComposite.

* Handle two more types for DebugGlobalVariable

kIROp_RaytracingAccelerationStructureType and
kIROp_SamplerComparisonStateType had to be handled in
`emitDebugTypeImpl()`

* Fix format

* Refactor debug type emission to reduce duplication

Use IRSamplerStateTypeBase type check and fallback pattern instead of
separate cases for each opcode type.

* Fix compiler warning

* Simplify `emitDebugTypeImpl()` more

1 files changed, 23 insertions, 0 deletions

diff --git a/tests/spirv/debug-variable-scope.slang b/tests/spirv/debug-variable-scope.slang
new file mode 100644
index 000000000..946c1a08b
--- /dev/null
+++ b/tests/spirv/debug-variable-scope.slang
@@ -0,0 +1,23 @@
+//TEST:SIMPLE(filecheck=CHECK):-target spirv-asm -entry main -stage fragment -g2 -emit-spirv-directly
+
+Texture2D    testTex      :   register(t0);
+SamplerState testSampler  :   register(s0);
+
+struct PSIn
+{
+   float4 pos      : SV_Position;
+};
+
+float4 main(PSIn input) : SV_TARGET
+{
+    uint4 testPos = input.pos;
+    float bias = -1.0;
+    float2 tc = testPos.xy / 32.0;
+    float4 colVal = testTex.SampleBias(testSampler, tc, bias);
+    return float4(colVal.xyz, 1.0);
+}
+
+// CHECK: %[[COMPILATION_UNIT_ID:[0-9]+]] = OpExtInst %void {{.*}} DebugCompilationUnit
+// CHECK: %[[FUNC_ID:[0-9]+]] = OpExtInst %void {{.*}} DebugFunction %{{[0-9]+}}
+// CHECK: DebugLocalVariable %{{[0-9]+}} %{{[0-9]+}} %{{[0-9]+}} %{{.*}} %{{.*}} %[[FUNC_ID]]
+// CHECK: DebugGlobalVariable %{{[0-9]+}} %{{[0-9]+}} %{{[0-9]+}} %{{.*}} %{{.*}} %[[COMPILATION_UNIT_ID]]