Revert suppression of __builtin_{read,write}_reversed for x86 and ARM,

for compatibility with earlier CompCert versions.
But don't use them in PackedStructs.


git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@2216 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e

1 files changed, 9 insertions, 2 deletions

diff --git a/ia32/Machregs.v b/ia32/Machregs.v
index a2f3c3e..31ea8ee 100644
--- a/ia32/Machregs.v
+++ b/ia32/Machregs.v
@@ -101,6 +101,11 @@ Definition destroyed_by_cond (cond: condition): list mreg :=
 Definition destroyed_by_jumptable: list mreg :=
   nil.
 
+Local Open Scope string_scope.
+
+Definition builtin_write16_reversed := ident_of_string "__builtin_write16_reversed".
+Definition builtin_write32_reversed := ident_of_string "__builtin_write32_reversed".
+
 Definition destroyed_by_builtin (ef: external_function): list mreg :=
   match ef with
   | EF_memcpy sz al =>
@@ -109,6 +114,10 @@ Definition destroyed_by_builtin (ef: external_function): list mreg :=
   | EF_vstore Mfloat32 => X7 :: nil
   | EF_vstore_global (Mint8unsigned|Mint8signed) _ _ => AX :: nil
   | EF_vstore_global Mfloat32 _ _ => X7 :: nil
+  | EF_builtin id sg =>
+      if ident_eq id builtin_write16_reversed
+      || ident_eq id builtin_write32_reversed
+      then CX :: DX :: nil else nil
   | _ => nil
   end.
 
@@ -131,8 +140,6 @@ Definition mregs_for_operation (op: operation): list (option mreg) * option mreg
   | _ => (nil, None)
   end.
 
-Local Open Scope string_scope.
-
 Definition builtin_negl := ident_of_string "__builtin_negl".
 Definition builtin_addl := ident_of_string "__builtin_addl".
 Definition builtin_subl := ident_of_string "__builtin_subl".