Add flag to supress warnings for splitting memory accesses

Author: sarranz

compiler/src/compile.ml

@@ -191,11 +191,14 @@ let compile (type reg regx xreg rflag cond asm_op extra_op)
           then Some (UseLea, "LEA instruction is used")
           else None
       | Split_memory_access ->
-          let msg =
-            "This memory immediate does not fit in one instruction, several \
-             instructions were issued."
-          in
-          Some (SplitMemoryAccess, msg)
+          if not !Glob_options.split_memory_access
+          then
+            let msg =
+              "This memory immediate does not fit in one instruction, several \
+               instructions were issued."
+            in
+            Some (SplitMemoryAccess, msg)
+          else None
     in
     let loc, _ = ii in
     Option.may (fun (w, msg) -> warning w loc "%s" msg) o;

compiler/src/glob_options.ml

@@ -25,6 +25,7 @@ type color = | Auto | Always | Never
 let color = ref Auto
 
 let lea = ref false
+let split_memory_access = ref false
 let set0 = ref false
 let model = ref Normal
 let print_stack_alloc = ref false
@@ -172,6 +173,9 @@ let options = [
     "-I"       , Arg.String set_idirs  , "[ident:path] Bind ident to path for from ident require ...";
     "-lea"     , Arg.Set lea           , " Use lea as much as possible (default is nolea)";
     "-nolea"   , Arg.Clear lea         , " Try to use add and mul instead of lea";
+    "-split-memory-access"
+      , Arg.Set split_memory_access
+      , " Split large memory accesses in several instructions";
     "-set0"     , Arg.Set set0          , " Use [xor x x] to set x to 0 (default is not)";
     "-noset0"   , Arg.Clear set0        , " Do not use set0 option";
     "-ec"       , Arg.String  set_ec    , "[f] Extract function [f] and its dependencies to an easycrypt file (deprecated)";