Doh! ENOPATCH. This time with attachments...
https://gcc.gnu.org/pipermail/gcc-patches/2021-August/576922.html
Roger
--
diff --git a/gcc/config/nvptx/nvptx.md b/gcc/config/nvptx/nvptx.md
index 108de1c..2b18f6a 100644
--- a/gcc/config/nvptx/nvptx.md
+++ b/gcc/config/nvptx/nvptx.md
@@ -614,6 +614,18 @@
""
"%.\\tmul.hi.s32\\t%0, %1, %2;")
+(define_insn "smuldi3_highpart"
+ [(set (match_operand:DI 0 "nvptx_register_operand" "=R")
+ (truncate:DI
+ (lshiftrt:TI
+ (mult:TI (sign_extend:TI
+ (match_operand:DI 1 "nvptx_register_operand" "R"))
+ (sign_extend:TI
+ (match_operand:DI 2 "nvptx_register_operand" "R")))
+ (const_int 64))))]
+ ""
+ "%.\\tmul.hi.s64\\t%0, %1, %2;")
+
(define_insn "umulhi3_highpart"
[(set (match_operand:HI 0 "nvptx_register_operand" "=R")
(truncate:HI
@@ -638,6 +650,18 @@
""
"%.\\tmul.hi.u32\\t%0, %1, %2;")
+(define_insn "umuldi3_highpart"
+ [(set (match_operand:DI 0 "nvptx_register_operand" "=R")
+ (truncate:DI
+ (lshiftrt:TI
+ (mult:TI (zero_extend:TI
+ (match_operand:DI 1 "nvptx_register_operand" "R"))
+ (zero_extend:TI
+ (match_operand:DI 2 "nvptx_register_operand" "R")))
+ (const_int 64))))]
+ ""
+ "%.\\tmul.hi.u64\\t%0, %1, %2;")
+
;; Shifts
(define_insn "ashl<mode>3"
diff --git a/gcc/expr.c b/gcc/expr.c
index b65cfcf..c032d54 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -8904,6 +8904,91 @@ expand_expr_divmod (tree_code code, machine_mode mode,
tree treeop0,
return expand_divmod (mod_p, code, mode, op0, op1, target, unsignedp);
}
+/* Helper function of expand_expr_real_2, to recognized and expand a
+ (rshift (mult (convert X) (convert Y)) INTEGER_CST) as a highpart
+ multiplication. This also handles multiplication by a constant. */
+
+static rtx
+try_expand_mult_highpart (sepops ops, rtx target, machine_mode tmode)
+{
+ tree stype = ops->type;
+ tree sarg0 = ops->op0;
+ tree sarg1 = ops->op1;
+
+ if (!INTEGRAL_TYPE_P (stype)
+ || TREE_CODE (sarg1) != INTEGER_CST
+ || TREE_CODE (sarg0) != SSA_NAME
+ || !tree_fits_uhwi_p (sarg1))
+ return NULL_RTX;
+
+ gimple *def = get_def_for_expr (sarg0, MULT_EXPR);
+ if (!def)
+ {
+ /* Allow NOP_EXPR between the multiplication and the rshift. */
+ def = get_def_for_expr (sarg0, NOP_EXPR);
+ if (def)
+ def = get_def_for_expr (gimple_assign_rhs1 (def), MULT_EXPR);
+ if (!def)
+ return NULL_RTX;
+ }
+
+ tree marg0 = gimple_assign_rhs1 (def);
+ tree mtype = TREE_TYPE (marg0);
+ if (!INTEGRAL_TYPE_P (mtype)
+ || TYPE_PRECISION (mtype) != TYPE_PRECISION (stype))
+ return NULL_RTX;
+
+ gimple *ldef = get_def_for_expr (marg0, NOP_EXPR);
+ if (!ldef)
+ return NULL_RTX;
+
+ tree lhs = gimple_assign_rhs1 (ldef);
+ tree ltype = TREE_TYPE (lhs);
+ bool unsignedp = TYPE_UNSIGNED (mtype);
+
+ if (TYPE_UNSIGNED (ltype) != unsignedp
+ || TYPE_PRECISION (ltype) != tree_to_uhwi (sarg1)
+ || TYPE_PRECISION (mtype) < 2 * TYPE_PRECISION (ltype))
+ return NULL_RTX;
+
+ tree marg1 = gimple_assign_rhs2 (def);
+ tree rhs;
+ if (TREE_CODE (marg1) == INTEGER_CST)
+ {
+ if (!int_fits_type_p (marg1, ltype))
+ return NULL_RTX;
+ rhs = fold_convert (ltype, marg1);
+ }
+ else
+ {
+ gimple *rdef = get_def_for_expr (marg1, NOP_EXPR);
+ if (!rdef)
+ return NULL_RTX;
+
+ rhs = gimple_assign_rhs1 (rdef);
+ if (TYPE_MAIN_VARIANT (ltype) != TYPE_MAIN_VARIANT (TREE_TYPE (rhs)))
+ return NULL_RTX;
+ }
+
+ machine_mode mode = TYPE_MODE (ltype);
+ optab tab = unsignedp ? umul_highpart_optab : smul_highpart_optab;
+ if (optab_handler (tab, mode) == CODE_FOR_nothing)
+ return NULL_RTX;
+
+ /* Commit to RTL expansion. */
+ rtx op0, op1, result;
+ expand_operands (lhs, rhs, NULL_RTX, &op0, &op1, EXPAND_NORMAL);
+ if (tmode != mode)
+ target = NULL_RTX;
+ result = expand_binop (mode, tab, op0, op1, target, unsignedp,
+ OPTAB_LIB_WIDEN);
+ if (!result)
+ return NULL_RTX;
+ if (tmode != mode)
+ result = convert_to_mode (tmode, result, TYPE_UNSIGNED (stype));
+ return result;
+}
+
rtx
expand_expr_real_2 (sepops ops, rtx target, machine_mode tmode,
enum expand_modifier modifier)
@@ -9771,6 +9856,14 @@ expand_expr_real_2 (sepops ops, rtx target, machine_mode
tmode,
if (ALL_FIXED_POINT_MODE_P (mode))
goto binop;
+ /* Try to use mul_highpart optab if available. */
+ if (code == RSHIFT_EXPR)
+ {
+ temp = try_expand_mult_highpart (ops, target, tmode);
+ if (temp)
+ return REDUCE_BIT_FIELD (temp);
+ }
+
if (! safe_from_p (subtarget, treeop1, 1))
subtarget = 0;
if (modifier == EXPAND_STACK_PARM)
/* { dg-do compile } */
/* { dg-options "-O2 -Wno-long-long" } */
typedef unsigned int __attribute ((mode(TI))) uti_t;
typedef int __attribute ((mode(TI))) ti_t;
long test1(long x, long y)
{
return ((ti_t)x * (ti_t)y) >> 64;
}
long test2(long x)
{
return ((ti_t)x * 19065) >> 64;
}
long test3(long x, long y)
{
return (uti_t)((ti_t)x * (ti_t)y) >> 64;
}
long test4(long x)
{
return (uti_t)((ti_t)x * 19065) >> 64;
}
ti_t test5(long x, long y)
{
return ((ti_t)x * (ti_t)y) >> 64;
}
ti_t test6(long x)
{
return ((ti_t)x * 19065) >> 64;
}
uti_t test7(long x, long y)
{
return (uti_t)((ti_t)x * (ti_t)y) >> 64;
}
uti_t test8(long x)
{
return (uti_t)((ti_t)x * 19065) >> 64;
}
/* { dg-final { scan-assembler-times "mul.hi.s64" 8 } } */
/* { dg-do compile } */
/* { dg-options "-O2 -Wno-long-long" } */
typedef unsigned int __attribute ((mode(TI))) uti_t;
typedef int __attribute ((mode(TI))) ti_t;
unsigned long test1(unsigned long x, unsigned long y)
{
return ((uti_t)x * (uti_t)y) >> 64;
}
unsigned long test2(unsigned long x)
{
return ((uti_t)x * 19065) >> 64;
}
unsigned long test3(unsigned long x, unsigned long y)
{
return (ti_t)((uti_t)x * (uti_t)y) >> 64;
}
unsigned long test4(unsigned long x)
{
return (ti_t)((uti_t)x * 19065) >> 64;
}
uti_t test5(unsigned long x, unsigned long y)
{
return ((uti_t)x * (uti_t)y) >> 64;
}
uti_t test6(unsigned long x)
{
return ((uti_t)x * 19065) >> 64;
}
ti_t test7(unsigned long x, unsigned long y)
{
return (ti_t)((uti_t)x * (uti_t)y) >> 64;
}
ti_t test8(unsigned long x)
{
return (ti_t)((uti_t)x * 19065) >> 64;
}
/* { dg-final { scan-assembler-times "mul.hi.u64" 8 } } */
