From 0e2c64ef4f9230507d59c9854bf4f7da69b7462b Mon Sep 17 00:00:00 2001
From: Virgile Prevosto <virgile.prevosto@m4x.org>
Date: Tue, 3 Mar 2020 19:27:30 +0100
Subject: [PATCH] [crowbar] less UB in generated expressions
---
tests/crowbar/constfold.ml | 43 +++++++++++++++++++-------------------
1 file changed, 21 insertions(+), 22 deletions(-)
diff --git a/tests/crowbar/constfold.ml b/tests/crowbar/constfold.ml
index 6adcf9fd6b3..b98c69153c1 100644
--- a/tests/crowbar/constfold.ml
+++ b/tests/crowbar/constfold.ml
@@ -19,9 +19,6 @@ let gen_type =
let mk_exp expr_node = { expr_loc = loc; expr_node }
-let force_int typ e =
- mk_exp (CAST (([SpecType typ],JUSTBASE), SINGLE_INIT e))
-
let needs_int_unary = function
| NOT | BNOT -> true
| _ -> false
@@ -75,22 +72,26 @@ let gen_constant =
mk_exp (CONSTANT (CONST_FLOAT (string_of_float f))))
]
+let mk_cast t e = mk_exp (CAST (([SpecType t],JUSTBASE), SINGLE_INIT e))
+
let protected_cast t e =
- match t with
- | Tunsigned ->
- mk_exp (
- QUESTION (
- mk_exp(BINARY(GE,e,mk_exp (CONSTANT(CONST_INT("0"))))),
- e,
- mk_exp(CONSTANT(CONST_INT("0")))))
- | _ ->
- let max = mk_exp (CONSTANT(CONST_INT("255"))) in
- let min = mk_exp (UNARY(MINUS,max)) in
- mk_exp(
- QUESTION(
- mk_exp(BINARY(GE,e,min)),
- mk_exp(QUESTION(mk_exp(BINARY(LE,e,max)),e,max)),
- min))
+ let max = mk_exp (CONSTANT(CONST_INT("255"))) in
+ let min =
+ match t with
+ | Tunsigned -> mk_exp(CONSTANT(CONST_INT("0")))
+ | _ -> mk_exp (UNARY(MINUS,max))
+ in
+ let maxr = mk_cast t max in
+ let minr = mk_cast t min in
+ mk_exp(
+ QUESTION(
+ mk_exp(BINARY(GE,e,min)),
+ mk_exp(QUESTION(mk_exp(BINARY(LE,e,max)),e,maxr)),
+ minr))
+
+let force_int typ e =
+ let e = protected_cast typ e in
+ mk_exp (CAST (([SpecType typ],JUSTBASE), SINGLE_INIT e))
let gen_expr =
fix
@@ -109,10 +110,8 @@ let gen_expr =
else e1,e2
in
mk_exp (BINARY (b,e1,e2)));
- map [ gen_int_type; gen_expr; gen_expr; gen_expr ]
- (fun t c et ef ->
- let c = force_int t c in
- mk_exp (QUESTION (c,et,ef)));
+ map [ gen_expr; gen_expr; gen_expr ]
+ (fun c et ef -> mk_exp (QUESTION (c,et,ef)));
map [ gen_type; gen_expr ]
(fun t e ->
let e = protected_cast t e in
--
GitLab