AArch64: Allow any offset for SVE addressing modes before reload.

On AArch64 aarch64_classify_address has a case for when it's non-strict
that will allow it to accept any byte offset from a reg when validating
an address in a given addressing mode.

This because reload would later make the address valid. SVE however requires
the address always be valid, but currently allows any address when a MEM +
offset is used.  This causes an ICE as nothing later forces the address to be
legitimate.

The patch forces aarch64_emit_sve_pred_move via expand_insn to ensure that
the addressing mode is valid for any loads/stores it creates, which follows
the SVE way of handling address classifications.

gcc/ChangeLog:

	PR target/88847
	* config/aarch64/aarch64-sve.md (*pred_mov<mode>, pred_mov<mode>):
	Expose as @aarch64_pred_mov.
	* config/aarch64/aarch64.c (aarch64_classify_address):
	Use expand_insn which legitimizes operands.

gcc/testsuite/ChangeLog:

	PR target/88847
	* gcc.target/aarch64/sve/pr88847.c: New test.

From-SVN: r268845

5 files changed, 42 insertions, 5 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index a6ef20c..76cef68 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2019-02-13  Tamar Christina  <tamar.christina@arm.com>
+
+	PR target/88847
+	* config/aarch64/aarch64-sve.md (*pred_mov<mode>, pred_mov<mode>):
+	Expose as @aarch64_pred_mov.
+	* config/aarch64/aarch64.c (aarch64_classify_address):
+	Use expand_insn which legitimizes operands.
+
 2019-02-13  Martin Liska  <mliska@suse.cz>
 
 	* builtins.h (expand_builtin_with_bounds): Remove declaration.
diff --git a/gcc/config/aarch64/aarch64-sve.md b/gcc/config/aarch64/aarch64-sve.md
index 703708b..3f39c4c 100644
--- a/gcc/config/aarch64/aarch64-sve.md
+++ b/gcc/config/aarch64/aarch64-sve.md
@@ -170,7 +170,7 @@
 ;; all-true.  Note that this pattern is generated directly by
 ;; aarch64_emit_sve_pred_move, so changes to this pattern will
 ;; need changes there as well.
-(define_insn_and_split "*pred_mov<mode>"
+(define_insn_and_split "@aarch64_pred_mov<mode>"
   [(set (match_operand:SVE_ALL 0 "nonimmediate_operand" "=w, w, m")
 	(unspec:SVE_ALL
 	  [(match_operand:<VPRED> 1 "register_operand" "Upl, Upl, Upl")
@@ -404,7 +404,7 @@
 
 ;; Predicated structure moves.  This works for both endiannesses but in
 ;; practice is only useful for big-endian.
-(define_insn_and_split "pred_mov<mode>"
+(define_insn_and_split "@aarch64_pred_mov<mode>"
   [(set (match_operand:SVE_STRUCT 0 "aarch64_sve_struct_nonimmediate_operand" "=w, w, Utx")
 	(unspec:SVE_STRUCT
 	  [(match_operand:<VPRED> 1 "register_operand" "Upl, Upl, Upl")
diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
index d7c453c..1fa28fe 100644
--- a/gcc/config/aarch64/aarch64.c
+++ b/gcc/config/aarch64/aarch64.c
@@ -3414,9 +3414,12 @@ aarch64_expand_mov_immediate (rtx dest, rtx imm,
 void
 aarch64_emit_sve_pred_move (rtx dest, rtx pred, rtx src)
 {
-  emit_insn (gen_rtx_SET (dest, gen_rtx_UNSPEC (GET_MODE (dest),
-						gen_rtvec (2, pred, src),
-						UNSPEC_MERGE_PTRUE)));
+  expand_operand ops[3];
+  machine_mode mode = GET_MODE (dest);
+  create_output_operand (&ops[0], dest, mode);
+  create_input_operand (&ops[1], pred, GET_MODE(pred));
+  create_input_operand (&ops[2], src, mode);
+  expand_insn (code_for_aarch64_pred_mov (mode), 3, ops);
 }
 
 /* Expand a pre-RA SVE data move from SRC to DEST in which at least one
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index d3223f0..5f220cc 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2019-02-13  Tamar Christina  <tamar.christina@arm.com>
+
+	PR target/88847
+	* gcc.target/aarch64/sve/pr88847.c: New test.
+
 2019-02-13  Jonathan Wakely  <jwakely@redhat.com>
 	    Jakub Jelinek  <jakub@redhat.com>
 
diff --git a/gcc/testsuite/gcc.target/aarch64/sve/pr88847.c b/gcc/testsuite/gcc.target/aarch64/sve/pr88847.c
new file mode 100644
index 0000000..b7504ad
--- /dev/null
+++ b/gcc/testsuite/gcc.target/aarch64/sve/pr88847.c
@@ -0,0 +1,21 @@
+/* { dg-do assemble { target aarch64_asm_sve_ok } } */
+/* { dg-additional-options "-O0 -msve-vector-bits=256 -mbig-endian --save-temps" } */
+
+typedef struct _b {
+  __attribute__((__vector_size__(32))) int a[2];
+} b;
+
+b *c;
+
+void
+foo (void)
+{
+  char *p = '\0';
+  b e = c[0];
+}
+
+/* { dg-final { scan-assembler {\tld1w\tz[0-9]+.s, p[0-9]+/z, \[x[0-9]+\]\n} } } */
+/* { dg-final { scan-assembler {\tld1w\tz[0-9]+.s, p[0-9]+/z, \[x[0-9]+, #1, mul vl\]\n} } } */
+/* { dg-final { scan-assembler {\tst1w\tz[0-9]+.s, p[0-9]+, \[(sp|x[0-9]+)\]\n} } } */
+/* { dg-final { scan-assembler {\tst1w\tz[0-9]+.s, p[0-9]+, \[(sp|x[0-9]+), #1, mul vl\]\n} } } */
+