From ccb720aa26d28b038fe3303f3b1d2c92024b56ce Mon Sep 17 00:00:00 2001
From: Alex Voicu <alexandru.voicu@amd.com>
Date: Thu, 23 Apr 2026 16:15:32 +0100
Subject: [PATCH 1/3] HIPSTDPAR fixes.

---
 lib/SPIRV/SPIRVReader.cpp | 31 ++++++++++++++++++++++++++++---
 1 file changed, 28 insertions(+), 3 deletions(-)

diff --git a/lib/SPIRV/SPIRVReader.cpp b/lib/SPIRV/SPIRVReader.cpp
index 10328cfb4..fed3de073 100644
--- a/lib/SPIRV/SPIRVReader.cpp
+++ b/lib/SPIRV/SPIRVReader.cpp
@@ -260,6 +260,10 @@ SPIRVErrorLog &SPIRVToLLVM::getErrorLog() { return BM->getErrorLog(); }
 void SPIRVToLLVM::setCallingConv(CallInst *Call) {
   Function *F = Call->getCalledFunction();
   assert(F && "Function pointers are not allowed in SPIRV");
+
+  if (M->getTargetTriple().isAMDGCN() &&
+      F->getCallingConv() == CallingConv::AMDGPU_KERNEL)
+    return Call->setCallingConv(CallingConv::C); // This is a stub call.
   Call->setCallingConv(F->getCallingConv());
 }
 
@@ -2827,10 +2831,31 @@ Value *SPIRVToLLVM::transValueWithoutDecoration(SPIRVValue *BV, Function *F,
   case OpFunctionCall: {
     SPIRVFunctionCall *BC = static_cast<SPIRVFunctionCall *>(BV);
     std::vector<Value *> Args = transValue(BC->getArgumentValues(), F, BB);
-    auto *Call = CallInst::Create(transFunction(BC->getFunction()), Args,
-                                  BC->getName(), BB);
-    setCallingConv(Call);
+    Function *Callee = transFunction(BC->getFunction());
+    if (M->getTargetTriple().isAMDGCN() && isKernel(BC->getFunction())) {
+      // In HIPSTDPAR mode we sometimes get some host side calls that have not
+      // yet been pruned (this happens later on reverse translated AMDGPU LLVM
+      // IR); whilst these are essentially dead, we should generate valid IR
+      // nonetheless, and this might require inserting an AS cast.
+      // TODO: we should only do this for HIPSTDPAR modules; this is a temporary
+      //       workaround.
+      std::transform(
+        Callee->arg_begin(), Callee->arg_end(), Args.begin(), Args.begin(),
+        [BB](auto &&Formal, auto &&Actual) {
+        if (!Formal.getType()->isPointerTy())
+          return Actual;
+
+        if (Formal.getType()->getPointerAddressSpace() ==
+            Actual->getType()->getPointerAddressSpace())
+          return Actual;
+
+        return cast<Value>(CastInst::CreatePointerBitCastOrAddrSpaceCast(
+            Actual, Formal.getType(), "", BB));
+      });
+    }
+    auto *Call = CallInst::Create(Callee, Args, BC->getName(), BB);
     setAttrByCalledFunc(Call);
+    setCallingConv(Call);
     applyFPFastMathModeDecorations(BV, Call);
     return mapValue(BV, Call);
   }

From b5730e3b353300aadf715b7fb79a702641ebcb78 Mon Sep 17 00:00:00 2001
From: Alex Voicu <alexandru.voicu@amd.com>
Date: Tue, 5 May 2026 23:34:25 +0100
Subject: [PATCH 2/3] Undo accidental removal.

---
 lib/SPIRV/SPIRVReader.cpp | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/lib/SPIRV/SPIRVReader.cpp b/lib/SPIRV/SPIRVReader.cpp
index aadd91edb..6a3e1c3af 100644
--- a/lib/SPIRV/SPIRVReader.cpp
+++ b/lib/SPIRV/SPIRVReader.cpp
@@ -2853,8 +2853,9 @@ Value *SPIRVToLLVM::transValueWithoutDecoration(SPIRVValue *BV, Function *F,
           return cast<Value>(CastInst::CreatePointerBitCastOrAddrSpaceCast(
               Actual, Formal.getType(), "", BB));
         });
-      } else if (BC->getFunction()->getName() == "llvm.amdgcn.is.shared" ||
-                 BC->getFunction()->getName() == "llvm.amdgcn.is.private") {
+      } else if (Args.size() == 1 &&
+                 (BC->getFunction()->getName() == "llvm.amdgcn.is.shared" ||
+                  BC->getFunction()->getName() == "llvm.amdgcn.is.private")) {
         if (BC->getArgumentValues().front()->getType()->getPointerStorageClass()
             != StorageClassGeneric) {
           auto *PTy = PointerType::get(
@@ -2866,8 +2867,8 @@ Value *SPIRVToLLVM::transValueWithoutDecoration(SPIRVValue *BV, Function *F,
       }
     }
     auto *Call = CallInst::Create(Callee, Args, BC->getName(), BB);
-    setAttrByCalledFunc(Call);
     setCallingConv(Call);
+    setAttrByCalledFunc(Call);
     applyFPFastMathModeDecorations(BV, Call);
     return mapValue(BV, Call);
   }

From 372aa6eed9313d5c84a8a526b5a720aca5362ce8 Mon Sep 17 00:00:00 2001
From: Alex Voicu <alexandru.voicu@amd.com>
Date: Fri, 8 May 2026 13:34:31 +0100
Subject: [PATCH 3/3] Remove vestigial noise.

---
 lib/SPIRV/SPIRVWriter.cpp | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/lib/SPIRV/SPIRVWriter.cpp b/lib/SPIRV/SPIRVWriter.cpp
index f7c7d786e..6006e99fc 100644
--- a/lib/SPIRV/SPIRVWriter.cpp
+++ b/lib/SPIRV/SPIRVWriter.cpp
@@ -856,10 +856,6 @@ SPIRVType *LLVMToSPIRVBase::transScavengedType(Value *V) {
                                    SPIRVEC_UnsupportedVarArgFunction);
 
     SPIRVType *RT = transType(FnTy->getReturnType());
-    if (M->getTargetTriple().getVendor() == Triple::VendorType::AMD)
-      if (F->getReturnType()->isPtrOrPtrVectorTy())
-        RT = transType(F->getReturnType()->getWithNewType(
-            PointerType::get(F->getContext(), SPIRAS_Constant)));
 
     std::vector<SPIRVType *> PT;
     for (Argument &Arg : F->args()) {