[AArch64] Fix ICE due to store_pair_lanes

The recently added store_pair_lanes causes ICEs in output_operand.
This is due to aarch64_classify_address treating it like a 128-bit STR
rather than a STP.  The valid immediate offsets don't fully overlap,
causing it to return false.  Eg. offset 264 is a valid 8-byte STP offset
but not a valid 16-byte STR offset since it isn't a multiple of 16.

The original instruction isn't passed in the printing code, so the context
is unclear.  The solution is to add a new operand formatting specifier
which is used for LDP/STP instructions like this.  This, like the Uml
constraint that applies to store_pair_lanes, uses PARALLEL when calling
aarch64_classify_address so that it knows it is an STP.
Also add the 'z' specifier for future use by load/store pair instructions.

    gcc/
	* config/aarch64/aarch64.c (aarch64_print_operand): Add new
	cases for printing LDP/STP memory addresses.
	(aarch64_print_address_internal): Renamed from
	aarch64_print_operand_address, added parameter, add Pmode check.
	(aarch64_print_ldpstp_address): New function for LDP/STP addresses.
	(aarch64_print_operand_address): Indirect to
	aarch64_print_address_internal.
	* config/aarch64/aarch64-simd.md (store_pair_lanes): Use new
	'y' operand output specifier.

From-SVN: r255230

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 51d7009..01d6a92 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,15 @@
+2017-11-29  Wilco Dijkstra  <wdijkstr@arm.com>
+
+       * config/aarch64/aarch64.c (aarch64_print_operand): Add new
+       cases for printing LDP/STP memory addresses.
+       (aarch64_print_address_internal): Renamed from
+       aarch64_print_operand_address, added parameter, add Pmode check.
+       (aarch64_print_ldpstp_address): New function for LDP/STP addresses.
+       (aarch64_print_operand_address): Indirect to
+       aarch64_print_address_internal.
+       * config/aarch64/aarch64-simd.md (store_pair_lanes): Use new
+       'y' operand output specifier.
+
 2017-11-29  Jakub Jelinek  <jakub@redhat.com>
 
        PR middle-end/83185

diff --git a/gcc/config/aarch64/aarch64-simd.md b/gcc/config/aarch64/aarch64-simd.md
index 3929973..02f0ff0 100644 (file)
--- a/gcc/config/aarch64/aarch64-simd.md
+++ b/gcc/config/aarch64/aarch64-simd.md
@@ -3047,8 +3047,8 @@
           (match_operand:VDC 2 "register_operand" "w, r")))]
   "TARGET_SIMD"
   "@
-   stp\\t%d1, %d2, %0
-   stp\\t%x1, %x2, %0"
+   stp\\t%d1, %d2, %y0
+   stp\\t%x1, %x2, %y0"
   [(set_attr "type" "neon_stp, store_16")]
 )
 

diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index 98221bb..904afa9 100644 (file)
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -150,6 +150,7 @@ static bool aarch64_builtin_support_vector_misalignment (machine_mode mode,
                                                         bool is_packed);
 static machine_mode
 aarch64_simd_container_mode (scalar_mode mode, unsigned width);
+static void aarch64_print_ldpstp_address (FILE *f, machine_mode mode, rtx x);
 
 /* Major revision number of the ARM Architecture implemented by the target.  */
 unsigned aarch64_architecture_version;
@@ -5225,7 +5226,11 @@ static const int aarch64_nzcv_codes[] =
      'L':              Output constant address specified by X
                        with a relocation offset if appropriate.
      'G':              Prints address of X, specifying a PC relative
-                       relocation mode if appropriate.  */
+                       relocation mode if appropriate.
+     'y':              Output address of LDP or STP - this is used for
+                       some LDP/STPs which don't use a PARALLEL in their
+                       pattern (so the mode needs to be adjusted).
+     'z':              Output address of a typical LDP or STP.  */
 
 static void
 aarch64_print_operand (FILE *f, rtx x, int code)
@@ -5427,8 +5432,6 @@ aarch64_print_operand (FILE *f, rtx x, int code)
 
        case MEM:
          output_address (GET_MODE (x), XEXP (x, 0));
-         /* Check all memory references are Pmode - even with ILP32.  */
-         gcc_assert (GET_MODE (XEXP (x, 0)) == Pmode);
          break;
 
        case CONST:
@@ -5592,18 +5595,48 @@ aarch64_print_operand (FILE *f, rtx x, int code)
       }
       break;
 
+    case 'y':
+    case 'z':
+      {
+       machine_mode mode = GET_MODE (x);
+
+       if (GET_CODE (x) != MEM)
+         {
+           output_operand_lossage ("invalid operand for '%%%c'", code);
+           return;
+         }
+
+       if (code == 'y')
+         {
+           /* LDP/STP which uses a single double-width memory operand.
+              Adjust the mode to appear like a typical LDP/STP.
+              Currently this is supported for 16-byte accesses only.  */
+           gcc_assert (GET_MODE_SIZE (mode) == 16);
+           mode = DFmode;
+         }
+
+       aarch64_print_ldpstp_address (f, mode, XEXP (x, 0));
+      }
+      break;
+
     default:
       output_operand_lossage ("invalid operand prefix '%%%c'", code);
       return;
     }
 }
 
+/* Print address 'x' of a memory access with mode 'mode'.
+   'op' is the context required by aarch64_classify_address.  It can either be
+   MEM for a normal memory access or PARALLEL for LDP/STP.  */
 static void
-aarch64_print_operand_address (FILE *f, machine_mode mode, rtx x)
+aarch64_print_address_internal (FILE *f, machine_mode mode, rtx x, RTX_CODE op)
 {
   struct aarch64_address_info addr;
 
-  if (aarch64_classify_address (&addr, x, mode, MEM, true))
+  /* Check all addresses are Pmode - including ILP32.  */
+  gcc_assert (GET_MODE (x) == Pmode);
+
+  if (aarch64_classify_address (&addr, x, mode, op, true))
     switch (addr.type)
       {
       case ADDRESS_REG_IMM:
@@ -5686,6 +5719,20 @@ aarch64_print_operand_address (FILE *f, machine_mode mode, rtx x)
   output_addr_const (f, x);
 }
 
+/* Print address 'x' of a LDP/STP with mode 'mode'.  */
+static void
+aarch64_print_ldpstp_address (FILE *f, machine_mode mode, rtx x)
+{
+  aarch64_print_address_internal (f, mode, x, PARALLEL);
+}
+
+/* Print address 'x' of a memory access with mode 'mode'.  */
+static void
+aarch64_print_operand_address (FILE *f, machine_mode mode, rtx x)
+{
+  aarch64_print_address_internal (f, mode, x, MEM);
+}
+
 bool
 aarch64_label_mentioned_p (rtx x)
 {