x86/sem: float_prev should not raise an Error

For instance, FSTP ST(0) will be translate (in parallel) to a drop of
ST(0) old value. This behavior should not raise an error.

1 files changed, 2 insertions, 1 deletions

diff --git a/miasm2/arch/x86/sem.py b/miasm2/arch/x86/sem.py
index 1c83fd02..2bc28abc 100644
--- a/miasm2/arch/x86/sem.py
+++ b/miasm2/arch/x86/sem.py
@@ -1733,7 +1733,8 @@ def float_prev(flt, popcount=1):
         return None
     i = float_list.index(flt)
     if i < popcount:
-        raise ValueError('broken index')
+        # Drop value (ex: FSTP ST(0))
+        return None
     flt = float_list[i - popcount]
     return flt