bit_cast & reinterpret warning if src->dst type not equally sized. (#3988)

* bit_cast & reinterpret warning if src->dst type not equally sized.

bit_cast & reinterpret warning if src->dst type not equally sized.

---------

Co-authored-by: Yong He <yonghe@outlook.com>

5 files changed, 30 insertions, 3 deletions

diff --git a/source/slang/slang-diagnostic-defs.h b/source/slang/slang-diagnostic-defs.h
index c2e76dffe..0c5d0f10c 100644
--- a/source/slang/slang-diagnostic-defs.h
+++ b/source/slang/slang-diagnostic-defs.h
@@ -744,6 +744,10 @@ DIAGNOSTIC(45001, Error, unresolvedSymbol, "unresolved external symbol '$0'.")
 DIAGNOSTIC(41201, Warning, expectDynamicUniformArgument, "argument for '$0' might not be a dynamic uniform, use `asDynamicUniform()` to silence this warning.")
 DIAGNOSTIC(41201, Warning, expectDynamicUniformValue, "value stored at this location must be dynamic uniform, use `asDynamicUniform()` to silence this warning.")
 
+
+DIAGNOSTIC(41202, Error, notEqualBitCastSize, "invalid to bit_cast differently sized types: '$0' with size '$1' casted into '$2' with size '$3'")
+DIAGNOSTIC(41203, Warning, notEqualReinterpretCastSize, "reinterpret<> into not equally sized types: '$0' with size '$1' casted into '$2' with size '$3'")
+
 //
 // 5xxxx - Target code generation.
 //
diff --git a/source/slang/slang-emit.cpp b/source/slang/slang-emit.cpp
index b7227a4f0..f492167a2 100644
--- a/source/slang/slang-emit.cpp
+++ b/source/slang/slang-emit.cpp
@@ -965,7 +965,7 @@ Result linkAndOptimizeIR(
 
     // Lower all bit_cast operations on complex types into leaf-level
     // bit_cast on basic types.
-    lowerBitCast(targetProgram, irModule);
+    lowerBitCast(targetProgram, irModule, sink);
 
     bool emitSpirvDirectly = targetProgram->getOptionSet().shouldEmitSPIRVDirectly();
 
diff --git a/source/slang/slang-ir-lower-bit-cast.cpp b/source/slang/slang-ir-lower-bit-cast.cpp
index 7a9f605d2..33516f54a 100644
--- a/source/slang/slang-ir-lower-bit-cast.cpp
+++ b/source/slang/slang-ir-lower-bit-cast.cpp
@@ -12,6 +12,7 @@ struct BitCastLoweringContext
     TargetProgram* targetProgram;
     IRModule* module;
     OrderedHashSet<IRInst*> workList;
+    DiagnosticSink* sink;
 
     void addToWorkList(IRInst* inst)
     {
@@ -212,8 +213,16 @@ struct BitCastLoweringContext
         auto operand = inst->getOperand(0);
         auto fromType = operand->getDataType();
         auto toType = inst->getDataType();
+
+        IRSizeAndAlignment toTypeSize;
+        getNaturalSizeAndAlignment(targetProgram->getOptionSet(), toType, &toTypeSize);
+        IRSizeAndAlignment fromTypeSize;
+        getNaturalSizeAndAlignment(targetProgram->getOptionSet(), fromType, &fromTypeSize);
+
         if (as<IRBasicType>(fromType) != nullptr && as<IRBasicType>(toType) != nullptr)
         {
+            if (fromTypeSize.size != toTypeSize.size)
+                sink->diagnose(inst->sourceLoc, Diagnostics::notEqualBitCastSize, fromType, fromTypeSize.size, toType, toTypeSize.size);
             // Both fromType and toType are basic types, no processing needed.
             return;
         }
@@ -238,6 +247,10 @@ struct BitCastLoweringContext
         {
             return;
         }
+
+        if (fromTypeSize.size != toTypeSize.size)
+            sink->diagnose(inst->sourceLoc, Diagnostics::notEqualBitCastSize, fromType, fromTypeSize.size, toType, toTypeSize.size);
+
         // Enumerate all fields in to-type and obtain its value from operand object.
         IRBuilder builder(module);
         builder.setInsertBefore(inst);
@@ -247,11 +260,12 @@ struct BitCastLoweringContext
     }
 };
 
-void lowerBitCast(TargetProgram* targetProgram, IRModule* module)
+void lowerBitCast(TargetProgram* targetProgram, IRModule* module, DiagnosticSink* sink)
 {
     BitCastLoweringContext context;
     context.module = module;
     context.targetProgram = targetProgram;
+    context.sink = sink;
     context.processModule();
 }
 
diff --git a/source/slang/slang-ir-lower-bit-cast.h b/source/slang/slang-ir-lower-bit-cast.h
index cb80d0dab..8c2547515 100644
--- a/source/slang/slang-ir-lower-bit-cast.h
+++ b/source/slang/slang-ir-lower-bit-cast.h
@@ -8,8 +8,9 @@ namespace Slang
 {
 
 struct IRModule;
+class DiagnosticSink;
 class TargetProgram;
 
-void lowerBitCast(TargetProgram* targetReq, IRModule* module);
+void lowerBitCast(TargetProgram* targetReq, IRModule* module, DiagnosticSink* sink);
 
 }
diff --git a/source/slang/slang-ir-lower-reinterpret.cpp b/source/slang/slang-ir-lower-reinterpret.cpp
index afc710539..34d4b77d9 100644
--- a/source/slang/slang-ir-lower-reinterpret.cpp
+++ b/source/slang/slang-ir-lower-reinterpret.cpp
@@ -60,15 +60,23 @@ struct ReinterpretLoweringContext
         auto fromType = operand->getDataType();
         auto toType = inst->getDataType();
         SlangInt fromTypeSize = getAnyValueSize(fromType);
+        bool cantPack = false;
         if (fromTypeSize < 0)
         {
+            cantPack = true;
             sink->diagnose(inst->sourceLoc, Slang::Diagnostics::typeCannotBePackedIntoAnyValue, fromType);
         }
         SlangInt toTypeSize = getAnyValueSize(toType);
         if (toTypeSize < 0)
         {
+            cantPack = true;
             sink->diagnose(inst->sourceLoc, Slang::Diagnostics::typeCannotBePackedIntoAnyValue, toType);
         }
+        if (fromTypeSize != toTypeSize
+            && cantPack == false)
+        {
+            sink->diagnose(inst->sourceLoc, Slang::Diagnostics::notEqualReinterpretCastSize, fromType, fromTypeSize, toType, toTypeSize);
+        }
         SlangInt anyValueSize = Math::Max(fromTypeSize, toTypeSize);
 
         IRBuilder builder(module);