From b286d66f7b687435f35c5d62286efd4906d8897a Mon Sep 17 00:00:00 2001 From: kub Date: Sat, 10 Oct 2020 09:44:15 +0200 Subject: [PATCH] sh2 drc, improve T bit propagation --- cpu/sh2/compiler.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/cpu/sh2/compiler.c b/cpu/sh2/compiler.c index 031223fe..d4844eac 100644 --- a/cpu/sh2/compiler.c +++ b/cpu/sh2/compiler.c @@ -6847,7 +6847,7 @@ end: // 2nd pass: some analysis lowest_literal = end_literals = lowest_mova = 0; - t = T_UNKNOWN; + t = T_UNKNOWN; // T flag state last_btarget = 0; op = 0; // delay/poll insns counter is_divop = 0; // divide op insns counter @@ -6857,7 +6857,7 @@ end: crc += FETCH_OP(pc); // propagate T (TODO: DIV0U) - if ((op_flags[i] & OF_BTARGET) || (opd->dest & BITMASK1(SHR_T))) + if (op_flags[i] & OF_BTARGET) t = T_UNKNOWN; if ((opd->op == OP_BRANCH_CT && t == T_SET) || @@ -6867,10 +6867,12 @@ end: } else if ((opd->op == OP_BRANCH_CT && t == T_CLEAR) || (opd->op == OP_BRANCH_CF && t == T_SET)) opd->op = OP_BRANCH_N; - else if ((opd->op == OP_SETCLRT && !opd->imm) || opd->op == OP_BRANCH_CT) - t = T_CLEAR; - else if ((opd->op == OP_SETCLRT && opd->imm) || opd->op == OP_BRANCH_CF) - t = T_SET; + else if (OP_ISBRACND(opd->op)) + t = (opd->op == OP_BRANCH_CF ? T_SET : T_CLEAR); + else if (opd->op == OP_SETCLRT) + t = (opd->imm ? T_SET : T_CLEAR); + else if (opd->dest & BITMASK1(SHR_T)) + t = T_UNKNOWN; // "overscan" detection: unreachable code after unconditional branch // this can happen if the insn after a forward branch isn't a local target -- 2.39.2