Fix ldshiftexp

* Fix the implementations and add tests
* Change shift from int63 to Z (was always used as a Z)
* Update FloatLemmas.v accordingly

Co-authored-by: Erik Martin-Dorel <erik.martin-dorel@irit.fr>

2 files changed, 21 insertions, 2 deletions

diff --git a/test-suite/primitive/float/frexp.v b/test-suite/primitive/float/frexp.v
index f13d5cebf6..2a600429b1 100644
--- a/test-suite/primitive/float/frexp.v
+++ b/test-suite/primitive/float/frexp.v
@@ -1,5 +1,3 @@
-(* TODO add tests for ldexp (particularly with overflow with 31 and 63 bits integers) *)
-
 Require Import ZArith Floats.
 
 Definition denorm := Eval compute in ldexp one (-1074)%Z.
diff --git a/test-suite/primitive/float/ldexp.v b/test-suite/primitive/float/ldexp.v
new file mode 100644
index 0000000000..a725deeeca
--- /dev/null
+++ b/test-suite/primitive/float/ldexp.v
@@ -0,0 +1,21 @@
+Require Import ZArith Int63 Floats.
+
+Check (eq_refl : ldexp one 9223372036854773807%Z = infinity).
+Check (eq_refl infinity <: ldexp one 9223372036854773807%Z = infinity).
+Check (eq_refl infinity <<: ldexp one 9223372036854773807%Z = infinity).
+
+Check (eq_refl : ldshiftexp one 9223372036854775807 = infinity).
+Check (eq_refl infinity <: ldshiftexp one 9223372036854775807 = infinity).
+Check (eq_refl infinity <<: ldshiftexp one 9223372036854775807 = infinity).
+
+Check (eq_refl : ldexp one (-2102) = 0%float).
+Check (eq_refl 0%float <: ldexp one (-2102) = 0%float).
+Check (eq_refl 0%float <<: ldexp one (-2102) = 0%float).
+
+Check (eq_refl : ldexp one (-3) = 0.125%float).
+Check (eq_refl 0.125%float <: ldexp one (-3) = 0.125%float).
+Check (eq_refl 0.125%float <<: ldexp one (-3) = 0.125%float).
+
+Check (eq_refl : ldexp one 3 = 8%float).
+Check (eq_refl 8%float <: ldexp one 3 = 8%float).
+Check (eq_refl 8%float <<: ldexp one 3 = 8%float).