fix testing if a OP_CALL's function is pure

kill_instruction() will kill an OP_CALL but only if it's a
forced kill or if the corresponding function is pure.

However, only functions called via a symbol pseudo are so killed.
Those called via a function pointer are not because only symbol
pseudos contain the function type needed to test the presence of
the MOD_PURE modifier.

Fix this by using the function type always available in the
instruction's ::fntypes member.

Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/simplify.c b/simplify.c
index 6caf6cbc..634a3ea6 100644
--- a/simplify.c
+++ b/simplify.c
@@ -351,9 +351,9 @@ int kill_insn(struct instruction *insn, int force)
 	case OP_CALL:
 		if (!force) {
 			/* a "pure" function can be killed too */
-			if (!(insn->func->type == PSEUDO_SYM))
-				return 0;
-			if (!(insn->func->sym->ctype.modifiers & MOD_PURE))
+			struct symbol *fntype = first_symbol(insn->fntypes);
+
+			if (!(fntype->ctype.modifiers & MOD_PURE))
 				return 0;
 		}
 		kill_use_list(insn->arguments);