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| author | Richard Henderson <rth@twiddle.net> | 2013-03-27 14:37:42 -0400 |
|---|---|---|
| committer | Richard Henderson <rth@twiddle.net> | 2013-04-05 13:35:41 -0500 |
| commit | 78c9f7c5b09408b4cac69a4fee97a118c8a89f6c (patch) | |
| tree | b98cf05a69b5cbff780e884e4b5964f8ac1d56fc /tcg/s390 | |
| parent | 0db921e6d8660a2491c173a2821e30924018d4bb (diff) | |
| download | qemu-78c9f7c5b09408b4cac69a4fee97a118c8a89f6c.zip qemu-78c9f7c5b09408b4cac69a4fee97a118c8a89f6c.tar.gz qemu-78c9f7c5b09408b4cac69a4fee97a118c8a89f6c.tar.bz2 | |
tcg-s390: Use all 20 bits of the offset in tcg_out_mem
This can save one insn, if the constant has any bits in 32-63 set,
but no bits in 21-31 set. It never results in more insns.
Signed-off-by: Richard Henderson <rth@twiddle.net>
Diffstat (limited to 'tcg/s390')
| -rw-r--r-- | tcg/s390/tcg-target.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/tcg/s390/tcg-target.c b/tcg/s390/tcg-target.c index 22927df..8e660b3 100644 --- a/tcg/s390/tcg-target.c +++ b/tcg/s390/tcg-target.c @@ -748,10 +748,11 @@ static void tcg_out_mem(TCGContext *s, S390Opcode opc_rx, S390Opcode opc_rxy, tcg_target_long ofs) { if (ofs < -0x80000 || ofs >= 0x80000) { - /* Combine the low 16 bits of the offset with the actual load insn; - the high 48 bits must come from an immediate load. */ - tcg_out_movi(s, TCG_TYPE_PTR, TCG_TMP0, ofs & ~0xffff); - ofs &= 0xffff; + /* Combine the low 20 bits of the offset with the actual load insn; + the high 44 bits must come from an immediate load. */ + tcg_target_long low = ((ofs & 0xfffff) ^ 0x80000) - 0x80000; + tcg_out_movi(s, TCG_TYPE_PTR, TCG_TMP0, ofs - low); + ofs = low; /* If we were already given an index register, add it in. */ if (index != TCG_REG_NONE) { |