Patchwork Add MULT_HIGHPART_EXPR

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Submitter Richard Henderson
Date June 27, 2012, 9:37 p.m.
Message ID <1340833028-3712-1-git-send-email-rth@redhat.com>
Download mbox | patch
Permalink /patch/167749/
State New
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Comments

Richard Henderson - June 27, 2012, 9:37 p.m.
I was sitting on this patch until I got around to fixing up Jakub's
existing vector divmod code to use it.  But seeing as how he's adding
more uses, I think it's better to get it in earlier.

Tested via a patch sent under separate cover that changes
__builtin_alpha_umulh to immediately fold to MULT_HIGHPART_EXPR.


r~

---

        * tree.def (MULT_HIGHPART_EXPR): New.
        * cfgexpand.c (expand_debug_expr): Ignore it.
        * expr.c (expand_expr_real_2): Handle it.
        * fold-const.c (int_const_binop_1): Likewise.
        * optabs.c (optab_for_tree_code): Likewise.
        * tree-cfg.c (verify_gimple_assign_binary): Likewise.
        * tree-inline.c (estimate_operator_cost): Likewise.
        * tree-pretty-print.c (dump_generic_node): Likewise.
        (op_code_prio, op_symbol_code): Likewise.
        * tree.c (commutative_tree_code): Likewise.  Also handle
        WIDEN_MULT_EXPR, VEC_WIDEN_MULT_HI_EXPR, VEC_WIDEN_MULT_LO_EXPR.
---
 gcc/ChangeLog           |   14 ++++++++++++++
 gcc/cfgexpand.c         |    6 +++++-
 gcc/expr.c              |    1 +
 gcc/fold-const.c        |   10 ++++++++++
 gcc/optabs.c            |    3 +++
 gcc/tree-cfg.c          |    1 +
 gcc/tree-inline.c       |    1 +
 gcc/tree-pretty-print.c |    5 +++++
 gcc/tree.c              |    4 ++++
 gcc/tree.def            |    4 ++++
 10 files changed, 48 insertions(+), 1 deletions(-)
Steven Bosscher - June 27, 2012, 9:42 p.m.
On Wed, Jun 27, 2012 at 11:37 PM, Richard Henderson <rth@redhat.com> wrote:
>        * tree.def (MULT_HIGHPART_EXPR): New.
>        * cfgexpand.c (expand_debug_expr): Ignore it.
>        * expr.c (expand_expr_real_2): Handle it.
>        * fold-const.c (int_const_binop_1): Likewise.
>        * optabs.c (optab_for_tree_code): Likewise.
>        * tree-cfg.c (verify_gimple_assign_binary): Likewise.
>        * tree-inline.c (estimate_operator_cost): Likewise.
>        * tree-pretty-print.c (dump_generic_node): Likewise.
>        (op_code_prio, op_symbol_code): Likewise.
>        * tree.c (commutative_tree_code): Likewise.  Also handle
>        WIDEN_MULT_EXPR, VEC_WIDEN_MULT_HI_EXPR, VEC_WIDEN_MULT_LO_EXPR.

Maybe also a bit in doc/generic.texi? Or is this not supposed to be
exposed to the front ends?

Ciao!
Steven

Patch

diff --git a/gcc/cfgexpand.c b/gcc/cfgexpand.c
index a8397c6..ad2f667 100644
--- a/gcc/cfgexpand.c
+++ b/gcc/cfgexpand.c
@@ -3415,7 +3415,7 @@  expand_debug_expr (tree exp)
     case VEC_PERM_EXPR:
       return NULL;
 
-   /* Misc codes.  */
+    /* Misc codes.  */
     case ADDR_SPACE_CONVERT_EXPR:
     case FIXED_CONVERT_EXPR:
     case OBJ_TYPE_REF:
@@ -3466,6 +3466,10 @@  expand_debug_expr (tree exp)
 	}
       return NULL;
 
+    case MULT_HIGHPART_EXPR:
+      /* ??? Similar to the above.  */
+      return NULL;
+
     case WIDEN_SUM_EXPR:
     case WIDEN_LSHIFT_EXPR:
       if (SCALAR_INT_MODE_P (GET_MODE (op0))
diff --git a/gcc/expr.c b/gcc/expr.c
index cad5b10..5295da2 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -8551,6 +8551,7 @@  expand_expr_real_2 (sepops ops, rtx target, enum machine_mode tmode,
       return expand_divmod (0, code, mode, op0, op1, target, unsignedp);
 
     case RDIV_EXPR:
+    case MULT_HIGHPART_EXPR:
       goto binop;
 
     case TRUNC_MOD_EXPR:
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 877cf32..702f4e0 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -999,6 +999,16 @@  int_const_binop_1 (enum tree_code code, const_tree arg1, const_tree arg2,
 			     &res.low, &res.high);
       break;
 
+    case MULT_HIGHPART_EXPR:
+      /* ??? Need quad precision, or an additional shift operand
+	 to the multiply primitive, to handle very large highparts.  */
+      if (TYPE_PRECISION (type) > HOST_BITS_PER_WIDE_INT)
+	return NULL_TREE;
+      tmp = double_int_mul (op1, op2);
+      res = double_int_rshift (tmp, TYPE_PRECISION (type),
+			       TYPE_PRECISION (type), !uns);
+      break;
+
     case TRUNC_DIV_EXPR:
     case FLOOR_DIV_EXPR: case CEIL_DIV_EXPR:
     case EXACT_DIV_EXPR:
diff --git a/gcc/optabs.c b/gcc/optabs.c
index 9a549ff..3094476 100644
--- a/gcc/optabs.c
+++ b/gcc/optabs.c
@@ -367,6 +367,9 @@  optab_for_tree_code (enum tree_code code, const_tree type,
     case BIT_XOR_EXPR:
       return xor_optab;
 
+    case MULT_HIGHPART_EXPR:
+      return TYPE_UNSIGNED (type) ? umul_highpart_optab : smul_highpart_optab;
+
     case TRUNC_MOD_EXPR:
     case CEIL_MOD_EXPR:
     case FLOOR_MOD_EXPR:
diff --git a/gcc/tree-cfg.c b/gcc/tree-cfg.c
index d7ab090..fe5af70 100644
--- a/gcc/tree-cfg.c
+++ b/gcc/tree-cfg.c
@@ -3731,6 +3731,7 @@  do_pointer_plus_expr_check:
       return false;
 
     case MULT_EXPR:
+    case MULT_HIGHPART_EXPR:
     case TRUNC_DIV_EXPR:
     case CEIL_DIV_EXPR:
     case FLOOR_DIV_EXPR:
diff --git a/gcc/tree-inline.c b/gcc/tree-inline.c
index 6746296..c3d3fb6 100644
--- a/gcc/tree-inline.c
+++ b/gcc/tree-inline.c
@@ -3379,6 +3379,7 @@  estimate_operator_cost (enum tree_code code, eni_weights *weights,
     case POINTER_PLUS_EXPR:
     case MINUS_EXPR:
     case MULT_EXPR:
+    case MULT_HIGHPART_EXPR:
     case FMA_EXPR:
 
     case ADDR_SPACE_CONVERT_EXPR:
diff --git a/gcc/tree-pretty-print.c b/gcc/tree-pretty-print.c
index f810d77..44d3c10 100644
--- a/gcc/tree-pretty-print.c
+++ b/gcc/tree-pretty-print.c
@@ -1612,6 +1612,7 @@  dump_generic_node (pretty_printer *buffer, tree node, int spc, int flags,
     case WIDEN_SUM_EXPR:
     case WIDEN_MULT_EXPR:
     case MULT_EXPR:
+    case MULT_HIGHPART_EXPR:
     case PLUS_EXPR:
     case POINTER_PLUS_EXPR:
     case MINUS_EXPR:
@@ -2674,6 +2675,7 @@  op_code_prio (enum tree_code code)
     case WIDEN_MULT_PLUS_EXPR:
     case WIDEN_MULT_MINUS_EXPR:
     case MULT_EXPR:
+    case MULT_HIGHPART_EXPR:
     case TRUNC_DIV_EXPR:
     case CEIL_DIV_EXPR:
     case FLOOR_DIV_EXPR:
@@ -2852,6 +2854,9 @@  op_symbol_code (enum tree_code code)
     case WIDEN_MULT_EXPR:
       return "w*";
 
+    case MULT_HIGHPART_EXPR:
+      return "h*";
+
     case NEGATE_EXPR:
     case MINUS_EXPR:
       return "-";
diff --git a/gcc/tree.c b/gcc/tree.c
index d3c2a19..1717d71 100644
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -6899,6 +6899,7 @@  commutative_tree_code (enum tree_code code)
     {
     case PLUS_EXPR:
     case MULT_EXPR:
+    case MULT_HIGHPART_EXPR:
     case MIN_EXPR:
     case MAX_EXPR:
     case BIT_IOR_EXPR:
@@ -6913,6 +6914,9 @@  commutative_tree_code (enum tree_code code)
     case TRUTH_AND_EXPR:
     case TRUTH_XOR_EXPR:
     case TRUTH_OR_EXPR:
+    case WIDEN_MULT_EXPR:
+    case VEC_WIDEN_MULT_HI_EXPR:
+    case VEC_WIDEN_MULT_LO_EXPR:
       return true;
 
     default:
diff --git a/gcc/tree.def b/gcc/tree.def
index 8a3007c..b0d4aea 100644
--- a/gcc/tree.def
+++ b/gcc/tree.def
@@ -639,6 +639,10 @@  DEFTREECODE (MULT_EXPR, "mult_expr", tcc_binary, 2)
    second operand is an integer of type sizetype.  */
 DEFTREECODE (POINTER_PLUS_EXPR, "pointer_plus_expr", tcc_binary, 2)
 
+/* Highpart multiplication.  For an integral type with precision B,
+   returns bits [2B-1, B] of the full 2*B product.  */
+DEFTREECODE (MULT_HIGHPART_EXPR, "mult_highpart_expr", tcc_binary, 2)
+
 /* Division for integer result that rounds the quotient toward zero.  */
 DEFTREECODE (TRUNC_DIV_EXPR, "trunc_div_expr", tcc_binary, 2)