arm: Annotate instructions with mve_safe_imp_xlane_pred

This patch annotates some MVE across lane instructions with a new attribute.
We use this attribute to let the compiler know that these instructions can be
safely implicitly predicated when tail predicating if their operands are
guaranteed to have zeroed tail predicated lanes.  These instructions were
selected because having the value 0 in those lanes or 'tail-predicating' those
lanes have the same effect.

gcc/ChangeLog:

	* config/arm/arm.md (mve_safe_imp_xlane_pred): New attribute.
	* config/arm/iterators.md (mve_vmaxmin_safe_imp): New iterator
	attribute.
	* config/arm/mve.md (vaddvq_s, vaddvq_u, vaddlvq_s, vaddlvq_u,
	vaddvaq_s, vaddvaq_u, vmaxavq_s, vmaxvq_u, vmladavq_s, vmladavq_u,
	vmladavxq_s, vmlsdavq_s, vmlsdavxq_s, vaddlvaq_s, vaddlvaq_u,
	vmlaldavq_u, vmlaldavq_s, vmlaldavq_u, vmlaldavxq_s, vmlsldavq_s,
	vmlsldavxq_s, vrmlaldavhq_u, vrmlaldavhq_s, vrmlaldavhxq_s,
	vrmlsldavhq_s, vrmlsldavhxq_s, vrmlaldavhaq_s, vrmlaldavhaq_u,
	vrmlaldavhaxq_s, vrmlsldavhaq_s, vrmlsldavhaxq_s, vabavq_s, vabavq_u,
	vmladavaq_u, vmladavaq_s, vmladavaxq_s, vmlsdavaq_s, vmlsdavaxq_s,
	vmlaldavaq_s, vmlaldavaq_u, vmlaldavaxq_s, vmlsldavaq_s,
	vmlsldavaxq_s): Added mve_safe_imp_xlane_pred.

diff --git a/gcc/config/arm/arm.md b/gcc/config/arm/arm.md
index 81290e83818e14c63078adc08de584c883bbd28a..814e871acead42f508314e51d07fe3804f1d6e8d 100644 (file)
--- a/gcc/config/arm/arm.md
+++ b/gcc/config/arm/arm.md
@@ -130,6 +130,12 @@
 ; encode that it is a predicable instruction.
 (define_attr "mve_unpredicated_insn" "" (symbol_ref "CODE_FOR_nothing"))
 
+; An attribute used by the loop-doloop pass when determining whether it is
+; safe to predicate a MVE instruction, that operates across lanes, and was
+; previously not predicated.  The pass will still check whether all inputs
+; are predicated by the VCTP predication mask.
+(define_attr "mve_safe_imp_xlane_pred" "yes,no" (const_string "no"))
+
 ; LENGTH of an instruction (in bytes)
 (define_attr "length" ""
   (const_int 4))

diff --git a/gcc/config/arm/iterators.md b/gcc/config/arm/iterators.md
index 547d87f3bc8ec777d5666400383b358b8d169943..da49bd64f17d2a710d82e10b70faa39665b022b9 100644 (file)
--- a/gcc/config/arm/iterators.md
+++ b/gcc/config/arm/iterators.md
@@ -869,6 +869,14 @@
                 (plus "vadd")
                 ])
 
+(define_int_attr mve_vmaxmin_safe_imp [
+                (VMAXVQ_U "yes")
+                (VMAXVQ_S "no")
+                (VMAXAVQ_S "yes")
+                (VMINVQ_U "no")
+                (VMINVQ_S "no")
+                (VMINAVQ_S "no")])
+
 (define_int_attr mve_cmp_op1 [
                 (VCMPCSQ_M_U "cs")
                 (VCMPEQQ_M_S "eq") (VCMPEQQ_M_U "eq")

diff --git a/gcc/config/arm/mve.md b/gcc/config/arm/mve.md
index 8aa0bded7f05f72022e83099b7a737691f85f4db..d7bdcd862f898081a4e08032ff1ffbd81f4f0d62 100644 (file)
--- a/gcc/config/arm/mve.md
+++ b/gcc/config/arm/mve.md
@@ -393,6 +393,7 @@
   "TARGET_HAVE_MVE"
   "<mve_insn>.<supf>%#<V_sz_elem>\t%0, %q1"
  [(set (attr "mve_unpredicated_insn") (symbol_ref "CODE_FOR_mve_<mve_insn>q_<supf><mode>"))
+  (set_attr "mve_safe_imp_xlane_pred" "yes")
   (set_attr "type" "mve_move")
 ])
 
@@ -529,6 +530,7 @@
   "TARGET_HAVE_MVE"
   "<mve_insn>.<supf>32\t%Q0, %R0, %q1"
  [(set (attr "mve_unpredicated_insn") (symbol_ref "CODE_FOR_mve_<mve_insn>q_<supf>v4si"))
+  (set_attr "mve_safe_imp_xlane_pred" "yes")
   (set_attr "type" "mve_move")
 ])
 
@@ -802,6 +804,7 @@
   "TARGET_HAVE_MVE"
   "<mve_insn>.<supf>%#<V_sz_elem>\t%0, %q2"
  [(set (attr "mve_unpredicated_insn") (symbol_ref "CODE_FOR_mve_<mve_insn>q_<supf><mode>"))
+  (set_attr "mve_safe_imp_xlane_pred" "yes")
   (set_attr "type" "mve_move")
 ])
 
@@ -1014,6 +1017,7 @@
   "TARGET_HAVE_MVE"
   "<mve_insn>.<supf>%#<V_sz_elem>\t%0, %q2"
  [(set (attr "mve_unpredicated_insn") (symbol_ref "CODE_FOR_mve_<mve_insn>q_<supf><mode>"))
+  (set_attr "mve_safe_imp_xlane_pred" "<mve_vmaxmin_safe_imp>")
   (set_attr "type" "mve_move")
 ])
 
@@ -1033,6 +1037,7 @@
   "TARGET_HAVE_MVE"
   "<mve_insn>.<supf>%#<V_sz_elem>\t%0, %q1, %q2"
  [(set (attr "mve_unpredicated_insn") (symbol_ref "CODE_FOR_mve_<mve_insn>q_<supf><mode>"))
+  (set_attr "mve_safe_imp_xlane_pred" "yes")
   (set_attr "type" "mve_move")
 ])
 
@@ -1219,6 +1224,7 @@
   "TARGET_HAVE_MVE"
   "<mve_insn>.<supf>32\t%Q0, %R0, %q2"
  [(set (attr "mve_unpredicated_insn") (symbol_ref "CODE_FOR_mve_<mve_insn>q_<supf>v4si"))
+  (set_attr "mve_safe_imp_xlane_pred" "yes")
   (set_attr "type" "mve_move")
 ])
 
@@ -1450,6 +1456,7 @@
   "TARGET_HAVE_MVE"
   "<mve_insn>.<supf>%#<V_sz_elem>\t%Q0, %R0, %q1, %q2"
  [(set (attr "mve_unpredicated_insn") (symbol_ref "CODE_FOR_mve_<mve_insn>q_<supf><mode>"))
+  (set_attr "mve_safe_imp_xlane_pred" "yes")
   (set_attr "type" "mve_move")
 ])
 
@@ -1588,6 +1595,7 @@
   "TARGET_HAVE_MVE"
   "<mve_insn>.<supf>32\t%Q0, %R0, %q1, %q2"
  [(set (attr "mve_unpredicated_insn") (symbol_ref "CODE_FOR_mve_<mve_insn>q_<supf>v4si"))
+  (set_attr "mve_safe_imp_xlane_pred" "yes")
   (set_attr "type" "mve_move")
 ])
 
@@ -1725,6 +1733,7 @@
   "TARGET_HAVE_MVE"
   "<mve_insn>.<supf>32\t%Q0, %R0, %q2, %q3"
  [(set (attr "mve_unpredicated_insn") (symbol_ref "CODE_FOR_mve_<mve_insn>q_<supf>v4si"))
+  (set_attr "mve_safe_imp_xlane_pred" "yes")
   (set_attr "type" "mve_move")
 ])
 
@@ -1742,6 +1751,7 @@
   "TARGET_HAVE_MVE"
   "<mve_insn>.<supf>%#<V_sz_elem>\t%0, %q2, %q3"
  [(set (attr "mve_unpredicated_insn") (symbol_ref "CODE_FOR_mve_<mve_insn>q_<supf><mode>"))
+  (set_attr "mve_safe_imp_xlane_pred" "yes")
   (set_attr "type" "mve_move")
 ])
 
@@ -1952,6 +1962,7 @@
   "TARGET_HAVE_MVE"
   "<mve_insn>.<supf>%#<V_sz_elem>\t%0, %q2, %q3"
  [(set (attr "mve_unpredicated_insn") (symbol_ref "CODE_FOR_mve_<mve_insn>q_<supf><mode>"))
+  (set_attr "mve_safe_imp_xlane_pred" "yes")
   (set_attr "type" "mve_move")
 ])
 
@@ -2401,6 +2412,7 @@
   "TARGET_HAVE_MVE"
   "<mve_insn>.<supf>%#<V_sz_elem>\t%Q0, %R0, %q2, %q3"
  [(set (attr "mve_unpredicated_insn") (symbol_ref "CODE_FOR_mve_<mve_insn>q_<supf><mode>"))
+  (set_attr "mve_safe_imp_xlane_pred" "yes")
   (set_attr "type" "mve_move")
 ])