* sched-deps.c (sched_analyze_1): On STACK_REGS targets, x87, treat

	all writes to any stack register as a read/write dependency on
	FIRST_STACK_REG.
	(sched_analyze_2): Likewise, for reads from any stack register.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@98762 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 19 insertions, 0 deletions

diff --git a/gcc/sched-deps.c b/gcc/sched-deps.c
index 933d74da60c..6b54fc8fd93 100644
--- a/gcc/sched-deps.c
+++ b/gcc/sched-deps.c
@@ -534,6 +534,15 @@ sched_analyze_1 (struct deps *deps, rtx x, rtx insn)
     {
       regno = REGNO (dest);
 
+#ifdef STACK_REGS
+      /* Treat all writes to a stack register as modifying the TOS.  */
+      if (regno >= FIRST_STACK_REG && regno <= LAST_STACK_REG)
+	{
+	  SET_REGNO_REG_SET (reg_pending_uses, FIRST_STACK_REG);
+	  regno = FIRST_STACK_REG;
+	}
+#endif
+
       /* A hard reg in a wide mode may really be multiple registers.
          If so, mark all of them just like the first.  */
       if (regno < FIRST_PSEUDO_REGISTER)
@@ -684,6 +693,16 @@ sched_analyze_2 (struct deps *deps, rtx x, rtx insn)
     case REG:
       {
 	int regno = REGNO (x);
+
+#ifdef STACK_REGS
+      /* Treat all reads of a stack register as modifying the TOS.  */
+      if (regno >= FIRST_STACK_REG && regno <= LAST_STACK_REG)
+	{
+	  SET_REGNO_REG_SET (reg_pending_sets, FIRST_STACK_REG);
+	  regno = FIRST_STACK_REG;
+	}
+#endif
+
 	if (regno < FIRST_PSEUDO_REGISTER)
 	  {
 	    int i = hard_regno_nregs[regno][GET_MODE (x)];