This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

[ARM] ARM NEON support part 5/7: Stop vget_lane sign/zero-extending unnecessarily


This patch replaces the use of unspecs with meaningful RTL for vget_lane* intrinsics, which prevents unnecessary zero- and sign-extensions from being emitted when using them. (The NEON lane-extraction instructions are capable of performing the extensions themselves).

Also, the assembler output for 32-bit extractions is tweaked to use the more-correct ".32" type instead of ".f32", ".s32" or ".u32" as previously. The corresponding test cases are regenerated accordingly.

OK?

Julian

ChangeLog (vgetlane-sign-ext)

Julian Brown <julian@codesourcery.com>

    gcc/
    * config/arm/neon.md (V_ext): New mode attribute.
    (neon_vget_lane<mode>): Replace with define_expand.
    (neon_vget_lane<mode>_sext_internal)
    (neon_vget_lane<mode>_zext_internal): New define_insns for double
    and quad precision vectors.
    (neon_vget_lanedi): Add bounds check. Remove dead comment.
    * config/arm/neon.ml (get_lane): Make 32-bit get-lane intrinsics
    have typeless 32-bit result.

    gcc/testsuite/
    * gcc.target/arm/neon/*.c: Regenerate.
--- .pc/vgetlane-sign-ext/gcc/config/arm/neon.md	2007-06-02 13:46:53.000000000 -0700
+++ gcc/config/arm/neon.md	2007-06-02 13:47:02.000000000 -0700
@@ -266,6 +266,14 @@
                           (V2SF "SF") (V4SF "SF")
                           (DI "DI")   (V2DI "DI")])
 
+;; Element modes for vector extraction, padded up to register size.
+
+(define_mode_attr V_ext [(V8QI "SI") (V16QI "SI")
+			 (V4HI "SI") (V8HI "SI")
+			 (V2SI "SI") (V4SI "SI")
+			 (V2SF "SF") (V4SF "SF")
+			 (DI "DI") (V2DI "DI")])
+
 ;; Mode of pair of elements for each vector mode, to define transfer
 ;; size for structure lane/dup loads and stores.
 (define_mode_attr V_two_elem [(V8QI "HI") (V16QI "HI")
@@ -2385,63 +2393,71 @@
   DONE;
 })
 
-;; FIXME: 32-bit element sizes are a bit funky (should be output as .32 not
-;; .u32), but the assembler should cope with that.
-
-(define_insn "neon_vget_lane<mode>"
-  [(set (match_operand:<V_elem> 0 "s_register_operand" "=r")
-	(unspec:<V_elem> [(match_operand:VD 1 "s_register_operand" "w")
-			  (match_operand:SI 2 "immediate_operand" "i")
-                          (match_operand:SI 3 "immediate_operand" "i")]
-                         UNSPEC_VGET_LANE))]
+(define_insn "neon_vget_lane<mode>_sext_internal"
+  [(set (match_operand:SI 0 "s_register_operand" "=r")
+	(sign_extend:SI
+	  (vec_select:<V_elem>
+	    (match_operand:VD 1 "s_register_operand" "w")
+	    (parallel [(match_operand:SI 2 "immediate_operand" "i")]))))]
   "TARGET_NEON"
-{
-  neon_lane_bounds (operands[2], 0, GET_MODE_NUNITS (<MODE>mode));
-  return "vmov%?.%t3%#<V_sz_elem>\t%0, %P1[%c2]";
-}
+  "vmov%?.s<V_sz_elem>\t%0, %P1[%c2]"
   [(set_attr "predicable" "yes")
    (set_attr "neon_type" "neon_bp_simple")]
 )
 
-; Operand 2 (lane number) is ignored because we can only extract the zeroth lane
-; with this insn. Operand 3 (info word) is ignored because it does nothing
-; useful with 64-bit elements.
+(define_insn "neon_vget_lane<mode>_zext_internal"
+  [(set (match_operand:SI 0 "s_register_operand" "=r")
+	(zero_extend:SI
+	  (vec_select:<V_elem>
+	    (match_operand:VD 1 "s_register_operand" "w")
+	    (parallel [(match_operand:SI 2 "immediate_operand" "i")]))))]
+  "TARGET_NEON"
+  "vmov%?.u<V_sz_elem>\t%0, %P1[%c2]"
+  [(set_attr "predicable" "yes")
+   (set_attr "neon_type" "neon_bp_simple")]
+)
 
-(define_insn "neon_vget_lanedi"
-  [(set (match_operand:DI 0 "s_register_operand" "=r")
-       (unspec:DI [(match_operand:DI 1 "s_register_operand" "w")
-                   (match_operand:SI 2 "immediate_operand" "i")
-                   (match_operand:SI 3 "immediate_operand" "i")]
-                  UNSPEC_VGET_LANE))]
+(define_insn "neon_vget_lane<mode>_sext_internal"
+  [(set (match_operand:SI 0 "s_register_operand" "=r")
+	(sign_extend:SI
+	  (vec_select:<V_elem>
+	    (match_operand:VQ 1 "s_register_operand" "w")
+	    (parallel [(match_operand:SI 2 "immediate_operand" "i")]))))]
   "TARGET_NEON"
 {
-  neon_lane_bounds (operands[2], 0, 1);
-  return "vmov%?\t%Q0, %R0, %P1  @ di";
+  rtx ops[3];
+  int regno = REGNO (operands[1]);
+  unsigned int halfelts = GET_MODE_NUNITS (<MODE>mode) / 2;
+  unsigned int elt = INTVAL (operands[2]);
+
+  ops[0] = operands[0];
+  ops[1] = gen_rtx_REG (<V_HALF>mode, regno + 2 * (elt / halfelts));
+  ops[2] = GEN_INT (elt % halfelts);
+  output_asm_insn ("vmov%?.s<V_sz_elem>\t%0, %P1[%c2]", ops);
+
+  return "";
 }
   [(set_attr "predicable" "yes")
    (set_attr "neon_type" "neon_bp_simple")]
 )
 
-(define_insn "neon_vget_lane<mode>"
-  [(set (match_operand:<V_elem> 0 "s_register_operand" "=r")
-       (unspec:<V_elem> [(match_operand:VQ 1 "s_register_operand" "w")
-                         (match_operand:SI 2 "immediate_operand" "i")
-                         (match_operand:SI 3 "immediate_operand" "i")]
-                        UNSPEC_VGET_LANE))]
+(define_insn "neon_vget_lane<mode>_zext_internal"
+  [(set (match_operand:SI 0 "s_register_operand" "=r")
+	(zero_extend:SI
+	  (vec_select:<V_elem>
+	    (match_operand:VQ 1 "s_register_operand" "w")
+	    (parallel [(match_operand:SI 2 "immediate_operand" "i")]))))]
   "TARGET_NEON"
 {
-  rtx ops[4];
+  rtx ops[3];
   int regno = REGNO (operands[1]);
   unsigned int halfelts = GET_MODE_NUNITS (<MODE>mode) / 2;
   unsigned int elt = INTVAL (operands[2]);
 
-  neon_lane_bounds (operands[2], 0, halfelts * 2);
-
   ops[0] = operands[0];
   ops[1] = gen_rtx_REG (<V_HALF>mode, regno + 2 * (elt / halfelts));
   ops[2] = GEN_INT (elt % halfelts);
-  ops[3] = operands[3];
-  output_asm_insn ("vmov%?.%t3%#<V_sz_elem>\t%0, %P1[%c2]", ops);
+  output_asm_insn ("vmov%?.u<V_sz_elem>\t%0, %P1[%c2]", ops);
 
   return "";
 }
@@ -2449,6 +2465,51 @@
    (set_attr "neon_type" "neon_bp_simple")]
 )
 
+(define_expand "neon_vget_lane<mode>"
+  [(match_operand:<V_ext> 0 "s_register_operand" "")
+   (match_operand:VDQW 1 "s_register_operand" "")
+   (match_operand:SI 2 "immediate_operand" "")
+   (match_operand:SI 3 "immediate_operand" "")]
+  "TARGET_NEON"
+{
+  HOST_WIDE_INT magic = INTVAL (operands[3]);
+  rtx insn;
+
+  neon_lane_bounds (operands[2], 0, GET_MODE_NUNITS (<MODE>mode));
+
+  if ((magic & 3) == 3 || GET_MODE_BITSIZE (GET_MODE_INNER (<MODE>mode)) == 32)
+    insn = gen_vec_extract<mode> (operands[0], operands[1], operands[2]);
+  else
+    {
+      if ((magic & 1) != 0)
+	insn = gen_neon_vget_lane<mode>_sext_internal (operands[0], operands[1],
+						       operands[2]);
+      else
+	insn = gen_neon_vget_lane<mode>_zext_internal (operands[0], operands[1],
+						       operands[2]);
+    }
+  emit_insn (insn);
+  DONE;
+})
+
+; Operand 3 (info word) is ignored because it does nothing useful with 64-bit
+; elements.
+
+(define_insn "neon_vget_lanedi"
+  [(set (match_operand:DI 0 "s_register_operand" "=r")
+       (unspec:DI [(match_operand:DI 1 "s_register_operand" "w")
+                   (match_operand:SI 2 "immediate_operand" "i")
+                   (match_operand:SI 3 "immediate_operand" "i")]
+                  UNSPEC_VGET_LANE))]
+  "TARGET_NEON"
+{
+  neon_lane_bounds (operands[2], 0, 1);
+  return "vmov%?\t%Q0, %R0, %P1  @ di";
+}
+  [(set_attr "predicable" "yes")
+   (set_attr "neon_type" "neon_bp_simple")]
+)
+
 (define_insn "neon_vget_lanev2di"
   [(set (match_operand:DI 0 "s_register_operand" "=r")
        (unspec:DI [(match_operand:V2DI 1 "s_register_operand" "w")
--- .pc/vgetlane-sign-ext/gcc/config/arm/neon.ml	2007-06-02 13:46:32.000000000 -0700
+++ gcc/config/arm/neon.ml	2007-06-02 13:47:02.000000000 -0700
@@ -611,7 +611,7 @@ let shift_insert shape elt =
 let get_lane shape elt =
   let vtype = type_for_elt shape elt in
   Arity2 (vtype 0, vtype 1, vtype 2),
-    (match elt with P8 -> U8 | P16 -> U16 | x -> x)
+    (match elt with P8 -> U8 | P16 -> U16 | S32 | U32 | F32 -> B32 | x -> x)
 
 let set_lane shape elt =
   let vtype = type_for_elt shape elt in

Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]