`reinterpret` and 16-bit value packing. (#1933)

* `reinterpret` and 16-bit value packing.

* Update `half-texture` cross-compile test reference result.

* Revert inadvertent reformatting of slang-ir-inst-defs.h

Co-authored-by: Yong He <yhe@nvidia.com>

1 files changed, 109 insertions, 0 deletions

diff --git a/source/slang/slang-ir-lower-reinterpret.cpp b/source/slang/slang-ir-lower-reinterpret.cpp
new file mode 100644
index 000000000..a140bacad
--- /dev/null
+++ b/source/slang/slang-ir-lower-reinterpret.cpp
@@ -0,0 +1,109 @@
+#include "slang-ir-lower-reinterpret.h"
+#include "slang-ir.h"
+#include "slang-ir-insts.h"
+#include "slang-ir-layout.h"
+#include "slang-ir-any-value-marshalling.h"
+
+namespace Slang
+{
+
+struct ReinterpretLoweringContext
+{
+    TargetRequest* targetReq;
+    DiagnosticSink* sink;
+    IRModule* module;
+    SharedIRBuilder sharedBuilderStorage;
+    OrderedHashSet<IRInst*> workList;
+
+    void addToWorkList(IRInst* inst)
+    {
+        for (auto ii = inst->getParent(); ii; ii = ii->getParent())
+        {
+            if (as<IRGeneric>(ii))
+                return;
+        }
+
+        if (workList.Contains(inst))
+            return;
+
+        workList.Add(inst);
+    }
+
+    void processInst(IRInst* inst)
+    {
+        switch (inst->getOp())
+        {
+        case kIROp_Reinterpret:
+            processReinterpret(inst);
+            break;
+        default:
+            break;
+        }
+    }
+
+    void processModule()
+    {
+        SharedIRBuilder* sharedBuilder = &sharedBuilderStorage;
+        sharedBuilder->module = module;
+        sharedBuilder->session = module->session;
+
+        // Deduplicate equivalent types.
+        sharedBuilder->deduplicateAndRebuildGlobalNumberingMap();
+
+        addToWorkList(module->getModuleInst());
+
+        while (workList.Count() != 0)
+        {
+            IRInst* inst = workList.getLast();
+
+            workList.removeLast();
+
+            processInst(inst);
+
+            for (auto child = inst->getLastChild(); child; child = child->getPrevInst())
+            {
+                addToWorkList(child);
+            }
+        }
+    }
+
+    void processReinterpret(IRInst* inst)
+    {
+        auto operand = inst->getOperand(0);
+        auto fromType = operand->getDataType();
+        auto toType = inst->getDataType();
+        SlangInt fromTypeSize = getAnyValueSize(fromType);
+        if (fromTypeSize < 0)
+        {
+            sink->diagnose(inst->sourceLoc, Slang::Diagnostics::typeCannotBePackedIntoAnyValue, fromType);
+        }
+        SlangInt toTypeSize = getAnyValueSize(toType);
+        if (toTypeSize < 0)
+        {
+            sink->diagnose(inst->sourceLoc, Slang::Diagnostics::typeCannotBePackedIntoAnyValue, toType);
+        }
+        SlangInt anyValueSize = Math::Max(fromTypeSize, toTypeSize);
+
+        IRBuilder builder;
+        builder.sharedBuilder = &sharedBuilderStorage;
+        builder.setInsertBefore(inst);
+        auto anyValueType = builder.getAnyValueType(builder.getIntValue(builder.getUIntType(), anyValueSize));
+        auto packInst = builder.emitPackAnyValue(
+            anyValueType,
+            operand);
+        auto unpackInst = builder.emitUnpackAnyValue(toType, packInst);
+        inst->replaceUsesWith(unpackInst);
+        inst->removeAndDeallocate();
+    }
+};
+
+void lowerReinterpret(TargetRequest* targetReq, IRModule* module, DiagnosticSink* sink)
+{
+    ReinterpretLoweringContext context;
+    context.module = module;
+    context.targetReq = targetReq;
+    context.sink = sink;
+    context.processModule();
+}
+
+}