[PATCH] lra: fix spill_hard_reg_in_range clobber check

[Ilya Leoshkevich]

Bootstrap and regtest are running on x86_64-redhat-linux.

Insns in FROM..TO range might not be recognized yet, and their
corresponding entries in lra_insn_recog_data[] might be NULLs.  In the
code from PR87596 the problematic insn is merely

    (note 148 154 68 7 NOTE_INSN_DELETED)

however I assume that non-note insns may occur as well.  So make sure
they are recognized before touching their lra_insn_recog_data_t.

gcc/ChangeLog:

2018-10-16  Ilya Leoshkevich  <i...@linux.ibm.com>

        PR rtl-optimization/87596
        * lra-constraints.c (spill_hard_reg_in_range): Use
        lra_get_insn_recog_data () instead of lra_insn_recog_data[]
        for instructions in FROM..TO range.

gcc/testsuite/ChangeLog:

2018-10-16  Ilya Leoshkevich  <i...@linux.ibm.com>

        PR rtl-optimization/87596
        * gcc.target/i386/pr87596.c: New test.
---
 gcc/lra-constraints.c                   |  3 ++-
 gcc/testsuite/gcc.target/i386/pr87596.c | 16 ++++++++++++++++
 2 files changed, 18 insertions(+), 1 deletion(-)
 create mode 100644 gcc/testsuite/gcc.target/i386/pr87596.c

diff --git a/gcc/lra-constraints.c b/gcc/lra-constraints.c
index 774d1ff3aaa..0d9cac07fb2 100644
--- a/gcc/lra-constraints.c
+++ b/gcc/lra-constraints.c
@@ -5696,10 +5696,11 @@ spill_hard_reg_in_range (int regno, enum reg_class 
rclass, rtx_insn *from, rtx_i
        continue;
       for (insn = from; insn != NEXT_INSN (to); insn = NEXT_INSN (insn))
        {
-         lra_insn_recog_data_t id = lra_insn_recog_data[uid = INSN_UID (insn)];
+         lra_insn_recog_data_t id = lra_get_insn_recog_data (insn);
          struct lra_static_insn_data *static_id = id->insn_static_data;
          struct lra_insn_reg *reg;
 
+         uid = INSN_UID (insn);
          if (bitmap_bit_p (&lra_reg_info[hard_regno].insn_bitmap, uid))
            break;
          for (reg = static_id->hard_regs; reg != NULL; reg = reg->next)
diff --git a/gcc/testsuite/gcc.target/i386/pr87596.c 
b/gcc/testsuite/gcc.target/i386/pr87596.c
new file mode 100644
index 00000000000..764708b694a
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr87596.c
@@ -0,0 +1,16 @@
+/* LRA corner case which triggered a segfault.  */
+/* Reduced testcase by Arseny Solokha.  */
+/* { dg-do compile { target int128 } } */
+/* { dg-options "-O1 -fschedule-insns -ftrapv -funroll-all-loops 
-fno-tree-dominator-opts -fno-tree-loop-im" } */
+    
+void
+wh (__int128 *ku)
+{
+  unsigned int *dp;
+
+  while (*ku < 1)
+    {
+      *dp <<= 32;  /* { dg-warning "left shift count >= width of type" } */
+      ++*ku;
+    }
+}
-- 
2.19.0