keep pimsim-nn happy

backend-simulators/pim/pim-simulator/src/lib/json_to_instruction/json_to_executor.rs

@@ -18,7 +18,7 @@ pub fn json_to_executor<'a>(
     mut cores: impl Iterator<Item = &'a Value>,
 ) -> Executable {
     let cell_precision = config.get("cell_precision").unwrap().as_i64().unwrap() as i32;
-    let core_cnt = config.get("core_cnt").unwrap().as_i64().unwrap() as i32;
+    let core_cnt = config.get("core_cnt").unwrap().as_i64().unwrap() as i32 - 1;
     let xbar_count = config.get("xbar_array_count").unwrap().as_i64().unwrap() as i32;
     let xbar_size = config.get("xbar_size").unwrap().as_array().unwrap();
     let rows_crossbar = xbar_size[0].as_i64().unwrap() as i32;

src/PIM/Compiler/PimCodeGen.cpp

@@ -651,7 +651,9 @@ static OnnxMlirCompilerErrorCodes writeConfigJson(func::FuncOp funcOp,
                                                   json::Object xbarsPerArrayGroup,
                                                   StringRef outputDirPath) {
   json::Object configJson;
-  configJson["core_cnt"] = coreCount;
+
+  // +1 because pimsim-nn also considers the host as a core
+  configJson["core_cnt"] = coreCount + 1;
 
   // TODO: Should this be based on the floating point type used in the model?
   // The 2 following values determine the bitwidth of the vectors' elements: bitwidth = adc_count * cell_precision
@@ -718,7 +720,8 @@ OnnxMlirCompilerErrorCodes onnx_mlir::compileToPimJson(ModuleOp& moduleOp, std::
     errs() << "Error while opening host core file `" << outputHostCorePath << "`: " << errorCode.message() << '\n';
     return InvalidOutputFileAccess;
   }
-  hostFileStream << "[]";
+  // The host core json contains 2 random instructions, just to make pimsim-nn happy
+  hostFileStream << "[{\"imm\":0,\"op\":\"sldi\",\"rd\":0},{\"imm\":0,\"op\":\"sldi\",\"rd\":0}]";
   hostFileStream.close();
 
   // For each core, specify the number of crossbar per array group.