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authorRichard Henderson <rth@twiddle.net>2013-09-11 13:44:17 -0700
committerRichard Henderson <rth@redhat.com>2014-04-16 12:12:58 -0400
commitd8918df577c9e3f2281d24c6c29d37df12bff2da (patch)
tree29f6124199ff595123b7d56a5c7386e466192be3 /tcg
parent4ec4f0bd564f79a7144fcaca59515a9c6cfc4577 (diff)
tcg-aarch64: Special case small constants in tcg_out_movi
Reviewed-by: Claudio Fontana <claudio.fontana@huawei.com> Signed-off-by: Richard Henderson <rth@twiddle.net>
Diffstat (limited to 'tcg')
-rw-r--r--tcg/aarch64/tcg-target.c10
1 files changed, 10 insertions, 0 deletions
diff --git a/tcg/aarch64/tcg-target.c b/tcg/aarch64/tcg-target.c
index c1d989571f..a08f6c782b 100644
--- a/tcg/aarch64/tcg-target.c
+++ b/tcg/aarch64/tcg-target.c
@@ -578,6 +578,16 @@ static void tcg_out_movi(TCGContext *s, TCGType type, TCGReg rd,
type = TCG_TYPE_I32;
}
+ /* Speed things up by handling the common case of small positive
+ and negative values specially. */
+ if ((value & ~0xffffull) == 0) {
+ tcg_out_insn(s, 3405, MOVZ, type, rd, value, 0);
+ return;
+ } else if ((ivalue & ~0xffffull) == 0) {
+ tcg_out_insn(s, 3405, MOVN, type, rd, ivalue, 0);
+ return;
+ }
+
/* Check for bitfield immediates. For the benefit of 32-bit quantities,
use the sign-extended value. That lets us match rotated values such
as 0xff0000ff with the same 64-bit logic matching 0xffffffffff0000ff. */