re PR target/83252 (Wrong code with "-march=skylake-avx512 -O3")

2017-12-07  Vladimir Makarov  <vmakarov@redhat.com>

	PR target/83252
	PR rtl-optimization/80818
	* lra.c (add_regs_to_insn_regno_info): Make a hard reg in CLOBBER
	always early clobbered.
	* lra-lives.c (process_bb_lives): Check input hard regs for early
	clobbered non-operand hard reg.

From-SVN: r255471

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 966810f..da13cd5 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2017-12-07  Vladimir Makarov  <vmakarov@redhat.com>
+
+       PR target/83252
+       PR rtl-optimization/80818
+       * lra.c (add_regs_to_insn_regno_info): Make a hard reg in CLOBBER
+       always early clobbered.
+       * lra-lives.c (process_bb_lives): Check input hard regs for early
+       clobbered non-operand hard reg.
+
 2017-12-07  Jakub Jelinek  <jakub@redhat.com>
 
        PR middle-end/83164

diff --git a/gcc/lra-lives.c b/gcc/lra-lives.c
index df7e253..785e436 100644 (file)
--- a/gcc/lra-lives.c
+++ b/gcc/lra-lives.c
@@ -928,7 +928,18 @@ process_bb_lives (basic_block bb, int &curr_point, bool dead_insn_p)
       for (reg = curr_static_id->hard_regs; reg != NULL; reg = reg->next)
        if (reg->type == OP_OUT
            && reg_early_clobber_p (reg, n_alt) && ! reg->subreg_p)
-         make_hard_regno_dead (reg->regno);
+         {
+           struct lra_insn_reg *reg2;
+           
+           /* We can have early clobbered non-operand hard reg and
+              the same hard reg as an insn input.  Don't make hard
+              reg dead before the insns.  */
+           for (reg2 = curr_id->regs; reg2 != NULL; reg2 = reg2->next)
+             if (reg2->type != OP_OUT && reg2->regno == reg->regno)
+               break;
+           if (reg2 == NULL)
+             make_hard_regno_dead (reg->regno);
+         }
 
       if (need_curr_point_incr)
        next_program_point (curr_point, freq);

diff --git a/gcc/lra.c b/gcc/lra.c
index 0d76eac..3fd15ee 100644 (file)
--- a/gcc/lra.c
+++ b/gcc/lra.c
@@ -1476,15 +1476,11 @@ add_regs_to_insn_regno_info (lra_insn_recog_data_t data, rtx x,
       add_regs_to_insn_regno_info (data, SET_SRC (x), insn, OP_IN, false, 0);
       break;
     case CLOBBER:
-      {
-       int code = INSN_CODE (insn);
-
-       /* We treat clobber of non-operand hard registers as early
-          clobber (the behavior is expected from asm).  */
-       add_regs_to_insn_regno_info (data, XEXP (x, 0), insn, OP_OUT,
-                                    code < 0, code < 0 ? ALL_ALTERNATIVES : 0);
-       break;
-      }
+      /* We treat clobber of non-operand hard registers as early
+        clobber.  */
+      add_regs_to_insn_regno_info (data, XEXP (x, 0), insn, OP_OUT,
+                                  true, ALL_ALTERNATIVES);
+      break;
     case PRE_INC: case PRE_DEC: case POST_INC: case POST_DEC:
       add_regs_to_insn_regno_info (data, XEXP (x, 0), insn, OP_INOUT, false, 0);
       break;