re PR target/84763 (ICE in i386_pe_seh_cold_init)

	PR target/84763
	* config/i386/winnt.c (i386_pe_seh_cold_init): Use small pre-allocation
	when the function accesses prior frames.

From-SVN: r258381

4 files changed, 52 insertions, 4 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 5675cdb..69b7def 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2018-03-09  Eric Botcazou  <ebotcazou@adacore.com>
+
+	PR target/84763
+	* config/i386/winnt.c (i386_pe_seh_cold_init): Use small pre-allocation
+	when the function accesses prior frames.
+
 2018-03-08  Jakub Jelinek  <jakub@redhat.com>
 
 	PR debug/84456
diff --git a/gcc/config/i386/winnt.c b/gcc/config/i386/winnt.c
index 9b406f4..d5c256b 100644
--- a/gcc/config/i386/winnt.c
+++ b/gcc/config/i386/winnt.c
@@ -879,7 +879,7 @@ void
 i386_pe_seh_cold_init (FILE *f, const char *name)
 {
   struct seh_frame_state *seh;
-  HOST_WIDE_INT offset;
+  HOST_WIDE_INT alloc_offset, offset;
 
   if (!TARGET_SEH)
     return;
@@ -891,7 +891,16 @@ i386_pe_seh_cold_init (FILE *f, const char *name)
   assemble_name (f, name);
   fputc ('\n', f);
 
-  offset = seh->sp_offset - INCOMING_FRAME_SP_OFFSET;
+  /* In the normal case, the frame pointer is near the bottom of the frame
+     so we can do the full stack allocation and set it afterwards.  There
+     is an exception when the function accesses prior frames so, in this
+     case, we need to pre-allocate a small chunk before setting it.  */
+  if (crtl->accesses_prior_frames)
+    alloc_offset = seh->cfa_offset;
+  else
+    alloc_offset = seh->sp_offset;
+
+  offset = alloc_offset - INCOMING_FRAME_SP_OFFSET;
   if (offset > 0 && offset < SEH_MAX_FRAME_SIZE)
     fprintf (f, "\t.seh_stackalloc\t" HOST_WIDE_INT_PRINT_DEC "\n", offset);
 
@@ -903,12 +912,12 @@ i386_pe_seh_cold_init (FILE *f, const char *name)
 		 : (gcc_unreachable (), "")), f);
 	print_reg (gen_rtx_REG (DImode, regno), 0, f);
 	fprintf (f, ", " HOST_WIDE_INT_PRINT_DEC "\n",
-		 seh->sp_offset - seh->reg_offset[regno]);
+		 alloc_offset - seh->reg_offset[regno]);
       }
 
   if (seh->cfa_reg != stack_pointer_rtx)
     {
-      offset = seh->sp_offset - seh->cfa_offset;
+      offset = alloc_offset - seh->cfa_offset;
 
       gcc_assert ((offset & 15) == 0);
       gcc_assert (IN_RANGE (offset, 0, 240));
@@ -918,6 +927,13 @@ i386_pe_seh_cold_init (FILE *f, const char *name)
       fprintf (f, ", " HOST_WIDE_INT_PRINT_DEC "\n", offset);
     }
 
+  if (crtl->accesses_prior_frames)
+    {
+      offset = seh->sp_offset - alloc_offset;
+      if (offset > 0 && offset < SEH_MAX_FRAME_SIZE)
+	fprintf (f, "\t.seh_stackalloc\t" HOST_WIDE_INT_PRINT_DEC "\n", offset);
+    }
+
   fputs ("\t.seh_endprologue\n", f);
 }
 
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 1917aef..80d60c8 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2018-03-09  Eric Botcazou  <ebotcazou@adacore.com>
+
+	* gcc.c-torture/compile/20180309-1.c: New test.
+
 2018-03-08  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/80598
diff --git a/gcc/testsuite/gcc.c-torture/compile/20180309-1.c b/gcc/testsuite/gcc.c-torture/compile/20180309-1.c
new file mode 100644
index 0000000..0784466
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/20180309-1.c
@@ -0,0 +1,22 @@
+/* PR target/84763 */
+/* { dg-require-effective-target return_address } */
+
+extern void abort (void);
+
+void *foo (unsigned int *data, unsigned int len)
+{
+  unsigned int local_data[128];
+
+  if (len > 128)
+    abort ();
+
+  for (unsigned int i = 0; i < len; i++)
+    local_data[i] = data[i] + data[len - 1 - i] * 2;
+
+  void *ret = __builtin_frame_address (0);
+
+  for (unsigned int i = 0; i < len; i++)
+    ret = ret + local_data[i] % 8;
+
+  return ret;
+}