From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf0-x244.google.com (mail-pf0-x244.google.com [IPv6:2607:f8b0:400e:c00::244]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 3xLLgf2PlfzDrKH for ; Mon, 31 Jul 2017 10:59:10 +1000 (AEST) Received: by mail-pf0-x244.google.com with SMTP id 72so4259139pfl.4 for ; Sun, 30 Jul 2017 17:59:10 -0700 (PDT) Received: from matt.ozlabs.ibm.com ([122.99.82.10]) by smtp.gmail.com with ESMTPSA id d127sm46851127pfa.171.2017.07.30.17.59.06 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Sun, 30 Jul 2017 17:59:07 -0700 (PDT) From: Matt Brown To: linuxppc-dev@lists.ozlabs.org Subject: [PATCH v4 5/5] powerpc/lib/sstep: Add isel instruction emulation Date: Mon, 31 Jul 2017 10:58:26 +1000 Message-Id: <20170731005826.32044-5-matthew.brown.dev@gmail.com> In-Reply-To: <20170731005826.32044-1-matthew.brown.dev@gmail.com> References: <20170731005826.32044-1-matthew.brown.dev@gmail.com> List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , This adds emulation for the isel instruction. Tested for correctness against the isel instruction and its extended mnemonics (lt, gt, eq) on ppc64le. Signed-off-by: Matt Brown --- v4: - simplify if statement to ternary op (same as isel emulation in kernel/traps.c) v2: - fixed opcode - fixed definition to include the 'if RA=0, a=0' clause - fixed ccr bitshifting error --- arch/powerpc/lib/sstep.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c index af4eef9..473bab5 100644 --- a/arch/powerpc/lib/sstep.c +++ b/arch/powerpc/lib/sstep.c @@ -1240,6 +1240,14 @@ int analyse_instr(struct instruction_op *op, struct pt_regs *regs, /* * Logical instructions */ + case 15: /* isel */ + mb = (instr >> 6) & 0x1f; /* bc */ + val = (regs->ccr >> (31 - mb)) & 1; + val2 = (ra) ? regs->gpr[ra] : 0; + + regs->gpr[rd] = (val) ? val2 : regs->gpr[rb]; + goto logical_done; + case 26: /* cntlzw */ asm("cntlzw %0,%1" : "=r" (regs->gpr[ra]) : "r" (regs->gpr[rd])); -- 2.9.3