[gcc r14-4448] [APX EGPR] middle-end: Add index_reg_class with insn argument.

[gcc r14-4448] [APX EGPR] middle-end: Add index_reg_class with insn argument.

[Hongyu Wang]

https://gcc.gnu.org/g:dfa15b4946d1d2678e0a3135c94173a103979f7d

commit r14-4448-gdfa15b4946d1d2678e0a3135c94173a103979f7d
Author: Hongyu Wang <hongyu.wang@intel.com>
Date:   Fri Jul 14 16:33:32 2023 +0800

    [APX EGPR] middle-end: Add index_reg_class with insn argument.
    
    Like base_reg_class, INDEX_REG_CLASS also does not support backend insn.
    Add index_reg_class with insn argument for lra/reload usage.
    
    gcc/ChangeLog:
    
            * addresses.h (index_reg_class): New wrapper function like
            base_reg_class.
            * doc/tm.texi: Document INSN_INDEX_REG_CLASS.
            * doc/tm.texi.in: Ditto.
            * lra-constraints.cc (index_part_to_reg): Pass index_class.
            (process_address_1): Calls index_reg_class with curr_insn and
            replace INDEX_REG_CLASS with its return value index_cl.
            * reload.cc (find_reloads_address): Likewise.
            (find_reloads_address_1): Likewise.
    
    Co-authored-by: Kong Lingling <lingling.kong@intel.com>
    Co-authored-by: Hongtao Liu <hongtao.liu@intel.com>

Diff:
---
 gcc/addresses.h        | 10 ++++++++++
 gcc/doc/tm.texi        |  8 ++++++++
 gcc/doc/tm.texi.in     |  8 ++++++++
 gcc/lra-constraints.cc | 17 +++++++++--------
 gcc/reload.cc          |  4 ++--
 5 files changed, 37 insertions(+), 10 deletions(-)

diff --git a/gcc/addresses.h b/gcc/addresses.h
index 2c92927bd51..08bf39cd56c 100644
--- a/gcc/addresses.h
+++ b/gcc/addresses.h
@@ -51,6 +51,16 @@ base_reg_class (machine_mode mode ATTRIBUTE_UNUSED,
 #endif
 }
 
+inline enum reg_class
+index_reg_class (rtx_insn *insn ATTRIBUTE_UNUSED = NULL)
+{
+#ifdef INSN_INDEX_REG_CLASS
+  return INSN_INDEX_REG_CLASS (insn);
+#else
+  return INDEX_REG_CLASS;
+#endif
+}
+
 /* Wrapper function to unify target macros REGNO_MODE_CODE_OK_FOR_BASE_P,
    REGNO_MODE_OK_FOR_REG_BASE_P, REGNO_MODE_OK_FOR_BASE_P and
    REGNO_OK_FOR_BASE_P.
diff --git a/gcc/doc/tm.texi b/gcc/doc/tm.texi
index 1958b3c9680..f7ac806ff15 100644
--- a/gcc/doc/tm.texi
+++ b/gcc/doc/tm.texi
@@ -2584,6 +2584,14 @@ address where its value is either multiplied by a scale factor or
 added to another register (as well as added to a displacement).
 @end defmac
 
+@defmac INSN_INDEX_REG_CLASS (@var{insn})
+A C expression whose value is the register class to which a valid
+index register for a specified @var{insn} must belong. This macro is
+used when some backend insns may have limited usage of index register
+compared with other insns. If you defined this macro, the compiler
+will use it instead of @code{INDEX_REG_CLASS}.
+@end defmac
+
 @defmac REGNO_OK_FOR_BASE_P (@var{num})
 A C expression which is nonzero if register number @var{num} is
 suitable for use as a base register in operand addresses.
diff --git a/gcc/doc/tm.texi.in b/gcc/doc/tm.texi.in
index 265b94c3673..141027e0bb4 100644
--- a/gcc/doc/tm.texi.in
+++ b/gcc/doc/tm.texi.in
@@ -2166,6 +2166,14 @@ address where its value is either multiplied by a scale factor or
 added to another register (as well as added to a displacement).
 @end defmac
 
+@defmac INSN_INDEX_REG_CLASS (@var{insn})
+A C expression whose value is the register class to which a valid
+index register for a specified @var{insn} must belong. This macro is
+used when some backend insns may have limited usage of index register
+compared with other insns. If you defined this macro, the compiler
+will use it instead of @code{INDEX_REG_CLASS}.
+@end defmac
+
 @defmac REGNO_OK_FOR_BASE_P (@var{num})
 A C expression which is nonzero if register number @var{num} is
 suitable for use as a base register in operand addresses.
diff --git a/gcc/lra-constraints.cc b/gcc/lra-constraints.cc
index 9105e00cad6..d10a2a3dc51 100644
--- a/gcc/lra-constraints.cc
+++ b/gcc/lra-constraints.cc
@@ -3399,12 +3399,12 @@ base_plus_disp_to_reg (struct address_info *ad, rtx disp)
 /* Make reload of index part of address AD.  Return the new
    pseudo.  */
 static rtx
-index_part_to_reg (struct address_info *ad)
+index_part_to_reg (struct address_info *ad, enum reg_class index_class)
 {
   rtx new_reg;
 
   new_reg = lra_create_new_reg (GET_MODE (*ad->index), NULL_RTX,
-				INDEX_REG_CLASS, NULL, "index term");
+				index_class, NULL, "index term");
   expand_mult (GET_MODE (*ad->index), *ad->index_term,
 	       GEN_INT (get_index_scale (ad)), new_reg, 1);
   return new_reg;
@@ -3659,13 +3659,14 @@ process_address_1 (int nop, bool check_only_p,
   /* If INDEX_REG_CLASS is assigned to base_term already and isn't to
      index_term, swap them so to avoid assigning INDEX_REG_CLASS to both
      when INDEX_REG_CLASS is a single register class.  */
+  enum reg_class index_cl = index_reg_class (curr_insn);
   if (ad.base_term != NULL
       && ad.index_term != NULL
-      && ira_class_hard_regs_num[INDEX_REG_CLASS] == 1
+      && ira_class_hard_regs_num[index_cl] == 1
       && REG_P (*ad.base_term)
       && REG_P (*ad.index_term)
-      && in_class_p (*ad.base_term, INDEX_REG_CLASS, NULL)
-      && ! in_class_p (*ad.index_term, INDEX_REG_CLASS, NULL))
+      && in_class_p (*ad.base_term, index_cl, NULL)
+      && ! in_class_p (*ad.index_term, index_cl, NULL))
     {
       std::swap (ad.base, ad.index);
       std::swap (ad.base_term, ad.index_term);
@@ -3689,7 +3690,7 @@ process_address_1 (int nop, bool check_only_p,
     }
   if (ad.index_term != NULL
       && process_addr_reg (ad.index_term, check_only_p,
-			   before, NULL, INDEX_REG_CLASS))
+			   before, NULL, index_cl))
     change_p = true;
 
   /* Target hooks sometimes don't treat extra-constraint addresses as
@@ -3798,7 +3799,7 @@ process_address_1 (int nop, bool check_only_p,
 					      GET_CODE (*ad.index),
 					      curr_insn);
 
-	  lra_assert (INDEX_REG_CLASS != NO_REGS);
+	  lra_assert (index_cl != NO_REGS);
 	  new_reg = lra_create_new_reg (Pmode, NULL_RTX, cl, NULL, "disp");
 	  lra_emit_move (new_reg, *ad.disp);
 	  *ad.inner = simplify_gen_binary (PLUS, GET_MODE (new_reg),
@@ -3894,7 +3895,7 @@ process_address_1 (int nop, bool check_only_p,
       changed pseudo on the equivalent memory and a subreg of the
       pseudo onto the memory of different mode for which the scale is
       prohibitted.  */
-      new_reg = index_part_to_reg (&ad);
+      new_reg = index_part_to_reg (&ad, index_cl);
       *ad.inner = simplify_gen_binary (PLUS, GET_MODE (new_reg),
 				       *ad.base_term, new_reg);
     }
diff --git a/gcc/reload.cc b/gcc/reload.cc
index dc33a83c6cf..2e57ebb3cac 100644
--- a/gcc/reload.cc
+++ b/gcc/reload.cc
@@ -5114,7 +5114,7 @@ find_reloads_address (machine_mode mode, rtx *memrefloc, rtx ad,
 	  /* Reload the displacement into an index reg.
 	     We assume the frame pointer or arg pointer is a base reg.  */
 	  find_reloads_address_part (XEXP (ad, 1), &XEXP (ad, 1),
-				     INDEX_REG_CLASS, GET_MODE (ad), opnum,
+				     index_reg_class (insn), GET_MODE (ad), opnum,
 				     type, ind_levels);
 	  return 0;
 	}
@@ -5514,7 +5514,7 @@ find_reloads_address_1 (machine_mode mode, addr_space_t as,
   bool reloaded_inner_of_autoinc = false;
 
   if (context == 1)
-    context_reg_class = INDEX_REG_CLASS;
+    context_reg_class = index_reg_class (insn);
   else
     context_reg_class = base_reg_class (mode, as, outer_code, index_code,
 					insn);