From 438d541dbe5fe7d7fe6b7aacaa6e6ef070c2e237 Mon Sep 17 00:00:00 2001
From: Bernhard Schommer <bernhardschommer@gmail.com>
Date: Thu, 16 Apr 2020 20:23:35 +0200
Subject: Move reserved_registers to CPragmas.

The list of reserved_registers is never reset between the compilation of
multiple files. Instead of storing them in IRC they are moved in the
CPragmas file and reset in the a new reset function for Cpragmas whic is
called per file.
---
 backend/IRC.ml        | 4 +---
 backend/IRC.mli       | 4 ----
 cfrontend/CPragmas.ml | 7 ++++++-
 driver/Frontend.ml    | 1 +
 4 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/backend/IRC.ml b/backend/IRC.ml
index b359da35..e94d6fbb 100644
--- a/backend/IRC.ml
+++ b/backend/IRC.ml
@@ -252,12 +252,10 @@ let class_of_loc = function
 
 let no_spill_class = 2
 
-let reserved_registers = ref ([]: mreg list)
-
 let rec remove_reserved = function
   | [] -> []
   | hd :: tl ->
-      if List.mem hd !reserved_registers
+      if List.mem hd !CPragmas.reserved_registers
       then remove_reserved tl
       else hd :: remove_reserved tl
 
diff --git a/backend/IRC.mli b/backend/IRC.mli
index 30b6d5c1..59471329 100644
--- a/backend/IRC.mli
+++ b/backend/IRC.mli
@@ -13,7 +13,6 @@
 (* Iterated Register Coalescing: George and Appel's graph coloring algorithm *)
 
 open Registers
-open Machregs
 open Locations
 open XTL
 
@@ -39,9 +38,6 @@ val add_pref: graph -> var -> var -> unit
 (* Color the graph.  Return an assignment of locations to variables. *)
 val coloring: graph -> (var -> loc)
 
-(* Machine registers that are reserved and not available for allocation. *)
-val reserved_registers: mreg list ref
-
 (* Auxiliaries to deal with register classes *)
 val class_of_type: AST.typ -> int
 val class_of_loc: loc -> int
diff --git a/cfrontend/CPragmas.ml b/cfrontend/CPragmas.ml
index 44660718..ce2cfcf0 100644
--- a/cfrontend/CPragmas.ml
+++ b/cfrontend/CPragmas.ml
@@ -49,13 +49,15 @@ let process_use_section_pragma classname id =
 
 (* #pragma reserve_register *)
 
+let reserved_registers = ref ([]: Machregs.mreg list)
+
 let process_reserve_register_pragma name =
   match Machregsaux.register_by_name name with
   | None ->
       C2C.error "unknown register in `reserve_register' pragma"
   | Some r ->
       if Machregsaux.can_reserve_register r then
-        IRC.reserved_registers := r :: !IRC.reserved_registers
+        reserved_registers := r :: !reserved_registers
       else
         C2C.error "cannot reserve this register (not a callee-save)"
 
@@ -84,5 +86,8 @@ let process_pragma name =
   | _ ->
       false
 
+let reset () =
+  reserved_registers := []
+
 let initialize () =
   C2C.process_pragma_hook := process_pragma
diff --git a/driver/Frontend.ml b/driver/Frontend.ml
index 74791247..bb97e945 100644
--- a/driver/Frontend.ml
+++ b/driver/Frontend.ml
@@ -75,6 +75,7 @@ let preprocess ifile ofile =
 let parse_c_file sourcename ifile =
   Debug.init_compile_unit sourcename;
   Sections.initialize();
+  CPragmas.reset();
   (* Simplification options *)
   let simplifs =
     "b" (* blocks: mandatory *)
-- 
cgit