From 64ce541c0bde7f8bcf8b39a08c32e71ceab23268 Mon Sep 17 00:00:00 2001 From: Aleksandar Markovic Date: Fri, 28 Jun 2019 12:43:38 +0200 Subject: [PATCH] linux-user: Handle EXCP_FPE properly for MIPS Handle EXCP_FPE properly for MIPS in cpu loop. Note that a vast majority of FP instructions are not affected by the absence of the code in this patch, as they use alternative code paths for handling floating point exceptions (see, for example, invocations of update_fcr31()) - they rely on softfloat library for keeping track on exceptions that needs to be raised. However, there are few MIPS FP instructions (an example is CTC1) that use function do_raise_exception() directly, and they need the case that is added in this patch to propagate the FPE exception as designed. The code is based on kernel's function force_fcr31_sig() in arch/mips/kernel.traps.c. Reported-by: Yunqiang Su Signed-off-by: Aleksandar Markovic Reviewed-by: Laurent Vivier Message-Id: <1561718618-20218-6-git-send-email-aleksandar.markovic@rt-rk.com> Signed-off-by: Laurent Vivier --- linux-user/mips/cpu_loop.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/linux-user/mips/cpu_loop.c b/linux-user/mips/cpu_loop.c index 43ba267547..0ba894fa7a 100644 --- a/linux-user/mips/cpu_loop.c +++ b/linux-user/mips/cpu_loop.c @@ -540,6 +540,23 @@ done_syscall: info.si_code = TARGET_ILL_ILLOPC; queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info); break; + case EXCP_FPE: + info.si_signo = TARGET_SIGFPE; + info.si_errno = 0; + info.si_code = TARGET_FPE_FLTUNK; + if (GET_FP_CAUSE(env->active_fpu.fcr31) & FP_INVALID) { + info.si_code = TARGET_FPE_FLTINV; + } else if (GET_FP_CAUSE(env->active_fpu.fcr31) & FP_DIV0) { + info.si_code = TARGET_FPE_FLTDIV; + } else if (GET_FP_CAUSE(env->active_fpu.fcr31) & FP_OVERFLOW) { + info.si_code = TARGET_FPE_FLTOVF; + } else if (GET_FP_CAUSE(env->active_fpu.fcr31) & FP_UNDERFLOW) { + info.si_code = TARGET_FPE_FLTUND; + } else if (GET_FP_CAUSE(env->active_fpu.fcr31) & FP_INEXACT) { + info.si_code = TARGET_FPE_FLTRES; + } + queue_signal(env, info.si_signo, QEMU_SI_FAULT, &info); + break; /* The code below was inspired by the MIPS Linux kernel trap * handling code in arch/mips/kernel/traps.c. */ -- 2.39.2