globals: make runtime parse simulation project directory environment variable which overwrites CL_CONTEXT_MPSIM_DEVICE_INTELFPGA

Author: sophimao

include/acl.h

@@ -266,6 +266,8 @@ typedef struct {
 
 /* Must match definition in aoc.pl */
 #define ACL_MPSIM_DEVICE_NAME "SimulatorDevice"
+/* Specifies which device simulator should simulate */
+#define ACL_MPSIM_PRJ_DIR "ACL_MPSIM_BOARD_SPEC_DIR"
 
 #define ACL_RAND_HASH_SIZE 40
 

src/acl_globals.cpp

@@ -108,7 +108,12 @@ const char *acl_get_offline_device_user_setting(int *use_offline_only_ret) {
     }
   } else {
     // Look for multi-process simulator before old simulator.
-    setting = acl_getenv("CL_CONTEXT_MPSIM_DEVICE_INTELFPGA");
+    // Check if simulation board spec directory is set, which shadows
+    // CL_CONTEXT_MPSIM_DEVICE_INTELFPGA
+    setting = acl_getenv(ACL_MPSIM_PRJ_DIR);
+    if (!setting) {
+      setting = acl_getenv("CL_CONTEXT_MPSIM_DEVICE_INTELFPGA");
+    }
     if (setting) {
       use_offline_only = ACL_CONTEXT_MPSIM;
       result = setting;