patch to fix PR88414

[Vladimir Makarov <vmakarov at redhat dot com>]

The following patch fixes

   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88414

The patch was bootstrapped and tested on x86-64.

Committed as rev. 267109.

Index: ChangeLog
===================================================================
--- ChangeLog	(revision 267108)
+++ ChangeLog	(working copy)
@@ -1,3 +1,14 @@
+2018-12-13  Vladimir Makarov  <vmakarov@redhat.com>
+
+	PR rtl-optimization/88414
+	* lra-int.h (lra_asm_error_p): New.
+	* lra-assigns.c (lra_assign): Check lra_asm_error_p for checking
+	call crossed pseudo assignment correctness.
+	(lra_split_hard_reg_for): Set up lra_asm_error_p.
+	* lra-constraints.c (curr_insn_transform): Ditto.
+	* lra.c (lra_asm_error_p): New.
+	(lra): Reset lra_asm_error_p.
+
 2018-12-13  Jakub Jelinek  <jakub@redhat.com>
 
 	PR rtl-optimization/88416
Index: lra-int.h
===================================================================
--- lra-int.h	(revision 266678)
+++ lra-int.h	(working copy)
@@ -288,6 +288,7 @@ typedef struct lra_insn_recog_data *lra_
 
 extern FILE *lra_dump_file;
 
+extern bool lra_asm_error_p;
 extern bool lra_reg_spill_p;
 
 extern HARD_REG_SET lra_no_alloc_regs;
Index: lra.c
===================================================================
--- lra.c	(revision 266678)
+++ lra.c	(working copy)
@@ -2334,6 +2334,9 @@ bitmap_head lra_subreg_reload_pseudos;
 /* File used for output of LRA debug information.  */
 FILE *lra_dump_file;
 
+/* True if we found an asm error.  */
+bool lra_asm_error_p;
+
 /* True if we should try spill into registers of different classes
    instead of memory.  */
 bool lra_reg_spill_p;
@@ -2371,7 +2374,8 @@ lra (FILE *f)
   bool live_p, inserted_p;
 
   lra_dump_file = f;
-
+  lra_asm_error_p = false;
+  
   timevar_push (TV_LRA);
 
   /* Make sure that the last insn is a note.  Some subsequent passes
Index: lra-constraints.c
===================================================================
--- lra-constraints.c	(revision 267108)
+++ lra-constraints.c	(working copy)
@@ -3940,6 +3940,7 @@ curr_insn_transform (bool check_only_p)
 	fatal_insn ("unable to generate reloads for:", curr_insn);
       error_for_asm (curr_insn,
 		     "inconsistent operand constraints in an %<asm%>");
+      lra_asm_error_p = true;
       /* Avoid further trouble with this insn.  Don't generate use
 	 pattern here as we could use the insn SP offset.  */
       lra_set_insn_deleted (curr_insn);
Index: lra-assigns.c
===================================================================
--- lra-assigns.c	(revision 266678)
+++ lra-assigns.c	(working copy)
@@ -1615,7 +1615,10 @@ lra_assign (bool &fails_p)
   bitmap_initialize (&all_spilled_pseudos, &reg_obstack);
   create_live_range_start_chains ();
   setup_live_pseudos_and_spill_after_risky_transforms (&all_spilled_pseudos);
-  if (flag_checking && !flag_ipa_ra)
+  if (! lra_asm_error_p && flag_checking && !flag_ipa_ra)
+    /* Check correctness of allocation for call-crossed pseudos but
+       only when there are no asm errors as in the case of errors the
+       asm is removed and it can result in incorrect allocation.  */
     for (i = FIRST_PSEUDO_REGISTER; i < max_regno; i++)
       if (lra_reg_info[i].nrefs != 0 && reg_renumber[i] >= 0
 	  && lra_reg_info[i].call_p
@@ -1783,7 +1786,7 @@ lra_split_hard_reg_for (void)
       insn = lra_insn_recog_data[u]->insn;
       if (asm_noperands (PATTERN (insn)) >= 0)
 	{
-	  asm_p = true;
+	  lra_asm_error_p = asm_p = true;
 	  error_for_asm (insn,
 			 "%<asm%> operand has impossible constraints");
 	  /* Avoid further trouble with this insn.
Index: testsuite/ChangeLog
===================================================================
--- testsuite/ChangeLog	(revision 267108)
+++ testsuite/ChangeLog	(working copy)
@@ -1,3 +1,8 @@
+2018-12-13  Vladimir Makarov  <vmakarov@redhat.com>
+
+	PR rtl-optimization/88414
+	* gcc.target/i386/pr88414.c: New.
+
 2018-12-13  Marek Polacek  <polacek@redhat.com>
 
 	PR c++/88216 - ICE with class type in non-type template parameter.
Index: testsuite/gcc.target/i386/pr88414.c
===================================================================
--- testsuite/gcc.target/i386/pr88414.c	(nonexistent)
+++ testsuite/gcc.target/i386/pr88414.c	(working copy)
@@ -0,0 +1,25 @@
+/* { dg-do compile } */
+/* { dg-options "-O1 -ftrapv" } */
+
+unsigned int
+foo (unsigned int *x, const unsigned int *y, int z, unsigned int w)
+{
+  unsigned int a, b, c, s;
+  int j;
+  j = -z;
+  x -= j;
+  y -= j;
+  a = 0;
+  do
+    {
+      asm volatile ("" : "=d" (b), "=d" (c) : "r" (y[j]), "d" (w)); /* { dg-error "'asm' operand has impossible constraints" } */
+      c += a;
+      a = (c < a) + b;
+      s = x[j];
+      c = s + c;
+      a += (c < s);
+      x[j] = c;
+    }
+  while (++j != 0);
+  return a;
+}