+Tue Apr 13 14:49:13 1999 Jan Hubicka <hubicka@freesoft.cz>
+
+ * i386.c (agi_dependent): Handle push operation more correctly.
+
Tue Apr 13 14:45:17 1999 Jan Hubicka <hubicka@freesoft.cz>
* i386.md (anddi3): Add % constraint.
agi_dependent (insn, dep_insn)
rtx insn, dep_insn;
{
+ int push = 0, push_dep = 0;
if (GET_CODE (dep_insn) == INSN
&& GET_CODE (PATTERN (dep_insn)) == SET
- && GET_CODE (SET_DEST (PATTERN (dep_insn))) == REG)
- return reg_mentioned_in_mem (SET_DEST (PATTERN (dep_insn)), insn);
+ && GET_CODE (SET_DEST (PATTERN (dep_insn))) == REG
+ && reg_mentioned_in_mem (SET_DEST (PATTERN (dep_insn)), insn))
+ return 1;
+
+ if (GET_CODE (insn) == INSN && GET_CODE (PATTERN (insn)) == SET
+ && GET_CODE (SET_DEST (PATTERN (insn))) == MEM
+ && push_operand (SET_DEST (PATTERN (insn)),
+ GET_MODE (SET_DEST (PATTERN (insn)))))
+ push = 1;
if (GET_CODE (dep_insn) == INSN && GET_CODE (PATTERN (dep_insn)) == SET
&& GET_CODE (SET_DEST (PATTERN (dep_insn))) == MEM
&& push_operand (SET_DEST (PATTERN (dep_insn)),
GET_MODE (SET_DEST (PATTERN (dep_insn)))))
- return reg_mentioned_in_mem (stack_pointer_rtx, insn);
+ push_dep = 1;
+
+ /* CPUs contain special hardware to allow two pushes. */
+ if (push && push_dep)
+ return 0;
+
+ /* Push operation implicitly change stack pointer causing AGI stalls. */
+ if (push_dep && reg_mentioned_in_mem (stack_pointer_rtx, insn))
+ return 1;
+
+ /* Push also implicitly read stack pointer. */
+ if (push && modified_in_p (stack_pointer_rtx, dep_insn))
+ return 1;
return 0;
}