WIP: Fixed inout struct and added testing for calls to non-differentiable functions (#2505)

* Added non-differentiable call test

* Extended testing for nondifferentiable calls

* Fixed subtle issue with extensions on generic types not applying the correct substitutions, leading to unspecialized generics at the emit stage

* More fixes. inout struct params now work fine

* Update inout-struct-parameters-jvp.slang

* Update slang-ir.cpp

* Fixed hoisting lookup_interface_method

* Fixed non-diff call return value

* Fixed issue with phi nodes

* Fixed problem with IRSpecialize preventing hoisitng of DifferentialPairType

* Fixed non-diff call test to conform to the new 'no_diff' system

1 files changed, 41 insertions, 8 deletions

diff --git a/source/slang/slang-ir.cpp b/source/slang/slang-ir.cpp
index de86a6a52..c12872320 100644
--- a/source/slang/slang-ir.cpp
+++ b/source/slang/slang-ir.cpp
@@ -3147,6 +3147,9 @@ namespace Slang
 
     IRInst* IRBuilder::emitMakeDifferentialPair(IRType* type, IRInst* primal, IRInst* differential)
     {
+        SLANG_RELEASE_ASSERT(as<IRDifferentialPairType>(type));
+        SLANG_RELEASE_ASSERT(as<IRDifferentialPairType>(type)->getValueType() != nullptr);
+
         IRInst* args[] = {primal, differential};
         auto inst = createInstWithTrailingArgs<IRMakeDifferentialPair>(
             this, kIROp_MakeDifferentialPair, type, 2, args);
@@ -3160,6 +3163,18 @@ namespace Slang
         UInt            argCount,
         IRInst* const*  args)
     {
+        auto innerReturnVal = findInnerMostGenericReturnVal(as<IRGeneric>(genericVal));
+
+        if (as<IRWitnessTable>(innerReturnVal))
+        {
+            return findOrEmitHoistableInst(
+                type,
+                kIROp_Specialize,
+                genericVal,
+                argCount,
+                args);
+        }
+
         auto inst = createInstWithTrailingArgs<IRSpecialize>(
             this,
             kIROp_Specialize,
@@ -3186,15 +3201,13 @@ namespace Slang
         //
         SLANG_ASSERT(witnessTableVal->getOp() != kIROp_StructKey);
 
-        auto inst = createInst<IRLookupWitnessMethod>(
-            this,
-            kIROp_lookup_interface_method,
-            type,
-            witnessTableVal,
-            interfaceMethodVal);
+        IRInst* args[] = {witnessTableVal, interfaceMethodVal};
 
-        addInst(inst);
-        return inst;
+        return findOrEmitHoistableInst(
+            type,
+            kIROp_lookup_interface_method,
+            2,
+            args);
     }
 
     IRInst* IRBuilder::emitGetSequentialIDInst(IRInst* rttiObj)
@@ -3467,6 +3480,15 @@ namespace Slang
             &diffPair);
     }
 
+    IRInst* IRBuilder::emitDifferentialPairAddressDifferential(IRType* diffType, IRInst* diffPair)
+    {
+        return emitIntrinsicInst(
+            diffType,
+            kIROp_DifferentialPairGetDifferential,
+            1,
+            &diffPair);
+    }
+
     IRInst* IRBuilder::emitDifferentialPairGetPrimal(IRInst* diffPair)
     {
         auto valueType = as<IRDifferentialPairType>(diffPair->getDataType())->getValueType();
@@ -3477,6 +3499,17 @@ namespace Slang
             &diffPair);
     }
 
+    IRInst* IRBuilder::emitDifferentialPairAddressPrimal(IRInst* diffPair)
+    {
+        auto valueType = as<IRDifferentialPairType>(
+            as<IRPtrTypeBase>(diffPair->getDataType())->getValueType())->getValueType();
+        return emitIntrinsicInst(
+            this->getPtrType(kIROp_PtrType, valueType),
+            kIROp_DifferentialPairGetPrimal,
+            1,
+            &diffPair);
+    }
+
     IRInst* IRBuilder::emitMakeMatrix(
         IRType*         type,
         UInt            argCount,