Cleanup definition of `printf`. (#5330)

* Cleanup definition of `printf`.

* Fix.

* Fix spirv generation.

* Fix.

* enhance test.

1 files changed, 21 insertions, 0 deletions

diff --git a/source/slang/slang-emit-glsl.cpp b/source/slang/slang-emit-glsl.cpp
index 7f8bc14b4..3ba967e20 100644
--- a/source/slang/slang-emit-glsl.cpp
+++ b/source/slang/slang-emit-glsl.cpp
@@ -2146,6 +2146,27 @@ bool GLSLSourceEmitter::tryEmitInstExprImpl(IRInst* inst, const EmitOpInfo& inOu
             m_writer->emit("endInvocationInterlockARB()");
             return true;
         }
+        case kIROp_Printf:
+        {
+            m_glslExtensionTracker->requireExtension(toSlice("GL_EXT_debug_printf"));
+            m_writer->emit("debugPrintfEXT(");
+            emitOperand(inst->getOperand(0), getInfo(EmitOp::General));
+            if (inst->getOperandCount() == 2)
+            {
+                auto operand = inst->getOperand(1);
+                if (auto makeStruct = as<IRMakeStruct>(operand))
+                {
+                    // Flatten the tuple resulting from the variadic pack.
+                    for (UInt bb = 0; bb < makeStruct->getOperandCount(); ++bb)
+                    {
+                        m_writer->emit(", ");
+                        emitOperand(makeStruct->getOperand(bb), getInfo(EmitOp::General));
+                    }
+                }
+            }
+            m_writer->emit(")");
+            return true;
+        }
         default: break;
     }