re PR debug/66691 (ICE on valid code at -O3 with -g enabled in simplify_subreg, at...

[gcc.git] / gcc / valtrack.c

diff --git a/gcc/valtrack.c b/gcc/valtrack.c
index 8318f7fdeff870b0c7219af65f6af9db59526682..80a0043196935469449731f367bafe5201420b8a 100644 (file)
--- a/gcc/valtrack.c
+++ b/gcc/valtrack.c
@@ -1,6 +1,6 @@
 /* Infrastructure for tracking user variable locations and values
    throughout compilation.
-   Copyright (C) 2010-2014 Free Software Foundation, Inc.
+   Copyright (C) 2010-2015 Free Software Foundation, Inc.
    Contributed by Alexandre Oliva <aoliva@redhat.com>.
 
 This file is part of GCC.
@@ -27,12 +27,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "predict.h"
 #include "basic-block.h"
 #include "valtrack.h"
-#include "hashtab.h"
-#include "hash-set.h"
-#include "vec.h"
-#include "machmode.h"
 #include "hard-reg-set.h"
-#include "input.h"
 #include "function.h"
 #include "regs.h"
 #include "emit-rtl.h"
@@ -534,6 +529,22 @@ dead_debug_add (struct dead_debug_local *debug, df_ref use, unsigned int uregno)
   bitmap_set_bit (debug->used, uregno);
 }
 
+/* Like lowpart_subreg, but if a subreg is not valid for machine, force
+   it anyway - for use in debug insns.  */
+
+static rtx
+debug_lowpart_subreg (machine_mode outer_mode, rtx expr,
+                     machine_mode inner_mode)
+{
+  if (inner_mode == VOIDmode)
+    inner_mode = GET_MODE (expr);
+  int offset = subreg_lowpart_offset (outer_mode, inner_mode);
+  rtx ret = simplify_gen_subreg (outer_mode, expr, inner_mode, offset);
+  if (ret)
+    return ret;
+  return gen_rtx_raw_SUBREG (outer_mode, expr, offset);
+}
+
 /* If UREGNO is referenced by any entry in DEBUG, emit a debug insn
    before or after INSN (depending on WHERE), that binds a (possibly
    global) debug temp to the widest-mode use of UREGNO, if WHERE is
@@ -655,16 +666,14 @@ dead_debug_insert_temp (struct dead_debug_local *debug, unsigned int uregno,
             the debug temp to.  ??? We could bind the debug_expr to a
             CONCAT or PARALLEL with the split multi-registers, and
             replace them as we found the corresponding sets.  */
-         else if (REGNO (reg) < FIRST_PSEUDO_REGISTER
-                  && (hard_regno_nregs[REGNO (reg)][GET_MODE (reg)]
-                      != hard_regno_nregs[REGNO (reg)][GET_MODE (dest)]))
+         else if (REG_NREGS (reg) != REG_NREGS (dest))
            breg = NULL;
          /* Ok, it's the same (hardware) REG, but with a different
             mode, so SUBREG it.  */
          else
-           breg = lowpart_subreg (GET_MODE (reg),
-                                  cleanup_auto_inc_dec (src, VOIDmode),
-                                  GET_MODE (dest));
+           breg = debug_lowpart_subreg (GET_MODE (reg),
+                                        cleanup_auto_inc_dec (src, VOIDmode),
+                                        GET_MODE (dest));
        }
       else if (GET_CODE (dest) == SUBREG)
        {
@@ -679,14 +688,14 @@ dead_debug_insert_temp (struct dead_debug_local *debug, unsigned int uregno,
             setting REG in its mode would, we won't know what to bind
             the debug temp to.  */
          else if (REGNO (reg) < FIRST_PSEUDO_REGISTER
-                  && (hard_regno_nregs[REGNO (reg)][GET_MODE (reg)]
+                  && (REG_NREGS (reg)
                       != hard_regno_nregs[REGNO (reg)][GET_MODE (dest)]))
            breg = NULL;
          /* Yay, we can use SRC, just adjust its mode.  */
          else
-           breg = lowpart_subreg (GET_MODE (reg),
-                                  cleanup_auto_inc_dec (src, VOIDmode),
-                                  GET_MODE (dest));
+           breg = debug_lowpart_subreg (GET_MODE (reg),
+                                        cleanup_auto_inc_dec (src, VOIDmode),
+                                        GET_MODE (dest));
        }
       /* Oh well, we're out of luck.  */
       else
@@ -740,7 +749,8 @@ dead_debug_insert_temp (struct dead_debug_local *debug, unsigned int uregno,
        *DF_REF_REAL_LOC (cur->use) = dval;
       else
        *DF_REF_REAL_LOC (cur->use)
-         = gen_lowpart_SUBREG (GET_MODE (*DF_REF_REAL_LOC (cur->use)), dval);
+         = debug_lowpart_subreg (GET_MODE (*DF_REF_REAL_LOC (cur->use)), dval,
+                                 GET_MODE (dval));
       /* ??? Should we simplify subreg of subreg?  */
       bitmap_set_bit (debug->to_rescan, INSN_UID (DF_REF_INSN (cur->use)));
       uses = cur->next;