[gcc(refs/users/meissner/heads/work137-vsubreg)] Peter's patches for subreg support.

[Michael Meissner <meissner@gcc.gnu.org>]

https://gcc.gnu.org/g:0eb03e85dccc79a68800150dd894a68af10dd187

commit 0eb03e85dccc79a68800150dd894a68af10dd187
Author: Michael Meissner <meissner@linux.ibm.com>
Date:   Fri Sep 29 01:44:28 2023 -0400

    Peter's patches for subreg support.
    
    2023-09-21  Peter Bergner  <bergner@linux.ibm.com>
    
    gcc/
    
            PR target/109116
            * gcc/config/rs6000/rs6000.cc (rs6000_modes_tieable_p): Make OOmdoe
            tieable with 128-bit vector modes.
    
    2023-09-15  Peter Bergner  <bergner@linux.ibm.com>
    
    gcc/
    
            PR target/109116
            * gcc/config/rs6000/mma.md (vsx_disassemble_pair): Use SUBREG's instead
            of UNSPEC's.
            (mma_disassemble_acc): Likewise.

Diff:
---
 gcc/config/rs6000/mma.md    | 50 ++++-----------------------------------------
 gcc/config/rs6000/rs6000.cc |  9 +++++---
 2 files changed, 10 insertions(+), 49 deletions(-)

diff --git a/gcc/config/rs6000/mma.md b/gcc/config/rs6000/mma.md
index b6cc7b28956..470dc2cca3a 100644
--- a/gcc/config/rs6000/mma.md
+++ b/gcc/config/rs6000/mma.md
@@ -405,29 +405,8 @@
    (match_operand 2 "const_0_to_1_operand")]
   "TARGET_MMA"
 {
-  rtx src;
-  int regoff = INTVAL (operands[2]);
-  src = gen_rtx_UNSPEC (V16QImode,
-			gen_rtvec (2, operands[1], GEN_INT (regoff)),
-			UNSPEC_MMA_EXTRACT);
-  emit_move_insn (operands[0], src);
-  DONE;
-})
-
-(define_insn_and_split "*vsx_disassemble_pair"
-  [(set (match_operand:V16QI 0 "mma_disassemble_output_operand" "=mwa")
-       (unspec:V16QI [(match_operand:OO 1 "vsx_register_operand" "wa")
-		      (match_operand 2 "const_0_to_1_operand")]
-		      UNSPEC_MMA_EXTRACT))]
-  "TARGET_MMA
-   && vsx_register_operand (operands[1], OOmode)"
-  "#"
-  "&& reload_completed"
-  [(const_int 0)]
-{
-  int reg = REGNO (operands[1]);
-  int regoff = INTVAL (operands[2]);
-  rtx src = gen_rtx_REG (V16QImode, reg + regoff);
+  int regoff = INTVAL (operands[2]) * GET_MODE_SIZE (V16QImode);
+  rtx src = simplify_gen_subreg (V16QImode, operands[1], OOmode, regoff);
   emit_move_insn (operands[0], src);
   DONE;
 })
@@ -479,29 +458,8 @@
    (match_operand 2 "const_0_to_3_operand")]
   "TARGET_MMA"
 {
-  rtx src;
-  int regoff = INTVAL (operands[2]);
-  src = gen_rtx_UNSPEC (V16QImode,
-			gen_rtvec (2, operands[1], GEN_INT (regoff)),
-			UNSPEC_MMA_EXTRACT);
-  emit_move_insn (operands[0], src);
-  DONE;
-})
-
-(define_insn_and_split "*mma_disassemble_acc"
-  [(set (match_operand:V16QI 0 "mma_disassemble_output_operand" "=mwa")
-       (unspec:V16QI [(match_operand:XO 1 "fpr_reg_operand" "d")
-		      (match_operand 2 "const_0_to_3_operand")]
-		      UNSPEC_MMA_EXTRACT))]
-  "TARGET_MMA
-   && fpr_reg_operand (operands[1], XOmode)"
-  "#"
-  "&& reload_completed"
-  [(const_int 0)]
-{
-  int reg = REGNO (operands[1]);
-  int regoff = INTVAL (operands[2]);
-  rtx src = gen_rtx_REG (V16QImode, reg + regoff);
+  int regoff = INTVAL (operands[2]) * GET_MODE_SIZE (V16QImode);
+  rtx src = simplify_gen_subreg (V16QImode, operands[1], XOmode, regoff);
   emit_move_insn (operands[0], src);
   DONE;
 })
diff --git a/gcc/config/rs6000/rs6000.cc b/gcc/config/rs6000/rs6000.cc
index ae7d7dbd621..3c6d7d86f5b 100644
--- a/gcc/config/rs6000/rs6000.cc
+++ b/gcc/config/rs6000/rs6000.cc
@@ -1964,9 +1964,12 @@ rs6000_hard_regno_mode_ok (unsigned int regno, machine_mode mode)
 static bool
 rs6000_modes_tieable_p (machine_mode mode1, machine_mode mode2)
 {
-  if (mode1 == PTImode || mode1 == OOmode || mode1 == XOmode
-      || mode2 == PTImode || mode2 == OOmode || mode2 == XOmode)
-    return mode1 == mode2;
+   if (mode1 == PTImode || mode1 == OOmode || mode1 == XOmode
+       || mode2 == PTImode || mode2 == XOmode)
+     return mode1 == mode2;
+ 
+  if (mode2 == OOmode)
+    return ALTIVEC_OR_VSX_VECTOR_MODE (mode1);
 
   if (ALTIVEC_OR_VSX_VECTOR_MODE (mode1))
     return ALTIVEC_OR_VSX_VECTOR_MODE (mode2);