From 78c9f7c5b09408b4cac69a4fee97a118c8a89f6c Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 27 Mar 2013 14:37:42 -0400 Subject: [PATCH] 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 --- tcg/s390/tcg-target.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/tcg/s390/tcg-target.c b/tcg/s390/tcg-target.c index 22927dfa26..8e660b318d 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) {