Hi,
Trunk gcc supports more constants to be built via two instructions: e.g.
"li/lis; xori/xoris/rldicl/rldicr/rldic".
And then num_insns_constant should also be updated.
Bootstrap & regtest pass ppc64{,le}.
Is this ok for trunk?
BR,
Jeff (Jiufu Guo)
gcc/ChangeLog:
* config/rs6000/rs6000.cc (can_be_built_by_lilis_and_rldicX): New
function.
(num_insns_constant_gpr): Update to return 2 for more cases.
(rs6000_emit_set_long_const): Update to use
can_be_built_by_lilis_and_rldicX.
---
gcc/config/rs6000/rs6000.cc | 64 ++++++++++++++++++++++++-------------
1 file changed, 41 insertions(+), 23 deletions(-)
diff --git a/gcc/config/rs6000/rs6000.cc b/gcc/config/rs6000/rs6000.cc
index cc24dd5301e..b23ff3d7917 100644
--- a/gcc/config/rs6000/rs6000.cc
+++ b/gcc/config/rs6000/rs6000.cc
@@ -6032,6 +6032,9 @@ direct_return (void)
return 0;
}
+static bool
+can_be_built_by_lilis_and_rldicX (HOST_WIDE_INT, int *, HOST_WIDE_INT *);
+
/* Helper for num_insns_constant. Calculate number of instructions to
load VALUE to a single gpr using combinations of addi, addis, ori,
oris, sldi and rldimi instructions. */
@@ -6044,35 +6047,41 @@ num_insns_constant_gpr (HOST_WIDE_INT value)
return 1;
/* constant loadable with addis */
- else if ((value & 0xffff) == 0
- && (value >> 31 == -1 || value >> 31 == 0))
+ if ((value & 0xffff) == 0 && (value >> 31 == -1 || value >> 31 == 0))
return 1;
/* PADDI can support up to 34 bit signed integers. */
- else if (TARGET_PREFIXED && SIGNED_INTEGER_34BIT_P (value))
+ if (TARGET_PREFIXED && SIGNED_INTEGER_34BIT_P (value))
return 1;
- else if (TARGET_POWERPC64)
- {
- HOST_WIDE_INT low = sext_hwi (value, 32);
- HOST_WIDE_INT high = value >> 31;
+ if (!TARGET_POWERPC64)
+ return 2;
- if (high == 0 || high == -1)
- return 2;
+ HOST_WIDE_INT low = sext_hwi (value, 32);
+ HOST_WIDE_INT high = value >> 31;
- high >>= 1;
+ if (high == 0 || high == -1)
+ return 2;
- if (low == 0 || low == high)
- return num_insns_constant_gpr (high) + 1;
- else if (high == 0)
- return num_insns_constant_gpr (low) + 1;
- else
- return (num_insns_constant_gpr (high)
- + num_insns_constant_gpr (low) + 1);
- }
+ high >>= 1;
- else
+ HOST_WIDE_INT ud2 = (low >> 16) & 0xffff;
+ HOST_WIDE_INT ud1 = low & 0xffff;
+ if (high == -1 && ((!(ud2 & 0x8000) && ud1 == 0) || (ud1 & 0x8000)))
+ return 2;
+ if (high == 0 && (ud1 == 0 || (!(ud1 & 0x8000))))
return 2;
+
+ int shift;
+ HOST_WIDE_INT mask;
+ if (can_be_built_by_lilis_and_rldicX (value, &shift, &mask))
+ return 2;
+
+ if (low == 0 || low == high)
+ return num_insns_constant_gpr (high) + 1;
+ if (high == 0)
+ return num_insns_constant_gpr (low) + 1;
+ return (num_insns_constant_gpr (high) + num_insns_constant_gpr (low) + 1);
}
/* Helper for num_insns_constant. Allow constants formed by the
@@ -10492,6 +10501,18 @@ can_be_built_by_li_and_rldic (HOST_WIDE_INT c, int
*shift, HOST_WIDE_INT *mask)
return false;
}
+/* Combine the above checking functions for li/lis;rldicX. */
+
+static bool
+can_be_built_by_lilis_and_rldicX (HOST_WIDE_INT c, int *shift,
+ HOST_WIDE_INT *mask)
+{
+ return (can_be_built_by_li_lis_and_rotldi (c, shift, mask)
+ || can_be_built_by_li_lis_and_rldicl (c, shift, mask)
+ || can_be_built_by_li_lis_and_rldicr (c, shift, mask)
+ || can_be_built_by_li_and_rldic (c, shift, mask));
+}
+
/* Subroutine of rs6000_emit_set_const, handling PowerPC64 DImode.
Output insns to set DEST equal to the constant C as a series of
lis, ori and shl instructions. */
@@ -10538,10 +10559,7 @@ rs6000_emit_set_long_const (rtx dest, HOST_WIDE_INT c)
emit_move_insn (dest, gen_rtx_XOR (DImode, temp,
GEN_INT ((ud2 ^ 0xffff) << 16)));
}
- else if (can_be_built_by_li_lis_and_rotldi (c, &shift, &mask)
- || can_be_built_by_li_lis_and_rldicl (c, &shift, &mask)
- || can_be_built_by_li_lis_and_rldicr (c, &shift, &mask)
- || can_be_built_by_li_and_rldic (c, &shift, &mask))
+ else if (can_be_built_by_lilis_and_rldicX (c, &shift, &mask))
{
temp = !can_create_pseudo_p () ? dest : gen_reg_rtx (DImode);
unsigned HOST_WIDE_INT imm = (c | ~mask);
--
2.25.1
