1 files changed, 16 insertions, 0 deletions
diff --git a/llvm/lib/Target/SPIRV/SPIRVPrepareFunctions.cpp b/llvm/lib/Target/SPIRV/SPIRVPrepareFunctions.cpp
index 4e4e6fb..be88f33 100644
--- a/llvm/lib/Target/SPIRV/SPIRVPrepareFunctions.cpp
+++ b/llvm/lib/Target/SPIRV/SPIRVPrepareFunctions.cpp
@@ -56,6 +56,13 @@ public:
   }
 };
 
+static cl::list<std::string> SPVAllowUnknownIntrinsics(
+    "spv-allow-unknown-intrinsics", cl::CommaSeparated,
+    cl::desc("Emit unknown intrinsics as calls to external functions. A "
+             "comma-separated input list of intrinsic prefixes must be "
+             "provided, and only intrinsics carrying a listed prefix get "
+             "emitted as described."),
+    cl::value_desc("intrinsic_prefix_0,intrinsic_prefix_1"), cl::ValueOptional);
 } // namespace
 
 char SPIRVPrepareFunctions::ID = 0;
@@ -445,6 +452,15 @@ bool SPIRVPrepareFunctions::substituteIntrinsicCalls(Function *F) {
                                        EraseFromParent);
         Changed = true;
         break;
+      default:
+        if (TM.getTargetTriple().getVendor() == Triple::AMD ||
+            any_of(SPVAllowUnknownIntrinsics, [II](auto &&Prefix) {
+              if (Prefix.empty())
+                return false;
+              return II->getCalledFunction()->getName().starts_with(Prefix);
+            }))
+          Changed |= lowerIntrinsicToFunction(II);
+        break;
       }
     }
   }