From: Aleksandar Markovic Date: Fri, 28 Jun 2019 10:43:38 +0000 (+0200) Subject: linux-user: Handle EXCP_FPE properly for MIPS X-Git-Tag: v4.1.0-rc0~24^2~1 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=64ce541c0bde7f8bcf8b39a08c32e71ceab23268;p=thirdparty%2Fqemu.git 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 --- diff --git a/linux-user/mips/cpu_loop.c b/linux-user/mips/cpu_loop.c index 43ba2675473..0ba894fa7aa 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. */