Unwanted partial constant propagation in 64-bit integer arguments to builtins

Here are two examples that cause an internal error in Asmexpand.ml:

volatile long long x; void f(unsigned int i) { x = i; }

unsigned g(unsigned i) { return __builtin_clzll(i); }

The argument "i" to builtin volatile store or __builtin_clzll is turned into a BA_splitlong(BA_int 0, BA <variable i>), which Asmexpand.ml doesn't know how to handle.

The fix (in AST.builtin_arg_ok) is to prevent this 'optimization' for all builtins except those of the "OK_all" kind, i.e. __builtin_annot.

Regression tests were added and tested on IA32.  Need to retest on ARM and PowerPC.

1 files changed, 1 insertions, 1 deletions

diff --git a/common/AST.v b/common/AST.v
index 0b524eb8..ae7178f4 100644
--- a/common/AST.v
+++ b/common/AST.v
@@ -684,7 +684,7 @@ Inductive builtin_arg_constraint : Type :=
 Definition builtin_arg_ok
        (A: Type) (ba: builtin_arg A) (c: builtin_arg_constraint) :=
   match ba, c with
-  | (BA _ | BA_splitlong _ _), _ => true
+  | (BA _ | BA_splitlong (BA _) (BA _)), _ => true
   | (BA_int _ | BA_long _ | BA_float _ | BA_single _), OK_const => true
   | BA_addrstack _, (OK_addrstack | OK_addrany) => true
   | BA_addrglobal _ _, (OK_addrglobal | OK_addrany) => true