From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:44882) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1XlNpM-0005f4-5n for qemu-devel@nongnu.org; Mon, 03 Nov 2014 15:02:23 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1XlNpD-00026E-12 for qemu-devel@nongnu.org; Mon, 03 Nov 2014 15:02:12 -0500 From: Tom Musta Date: Mon, 3 Nov 2014 14:01:11 -0600 Message-Id: <1415044877-17300-2-git-send-email-tommusta@gmail.com> In-Reply-To: <1415044877-17300-1-git-send-email-tommusta@gmail.com> References: <1415044877-17300-1-git-send-email-tommusta@gmail.com> Subject: [Qemu-devel] [PATCH 1/7] target-ppc: VXSQRT Should Not Be Set for NaNs List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org, qemu-ppc@nongnu.org Cc: pbonzini@redhat.com, agraf@suse.de, Tom Musta The Power ISA square root instructions (fsqrt[s], frsqrte[s]) must set the FPSCR[VXSQRT] flag when operating on a negative value. However, NaNs have no sign and therefore this flag should not be set when operating on one. Change the order of the checks in the helper code. Move the SNaN-to-QNaN macro to the top of the file so that it can be re-used. Signed-off-by: Tom Musta --- target-ppc/fpu_helper.c | 29 +++++++++++++++++------------ 1 files changed, 17 insertions(+), 12 deletions(-) diff --git a/target-ppc/fpu_helper.c b/target-ppc/fpu_helper.c index da93d12..288401d 100644 --- a/target-ppc/fpu_helper.c +++ b/target-ppc/fpu_helper.c @@ -19,6 +19,9 @@ #include "cpu.h" #include "exec/helper-proto.h" +#define float64_snan_to_qnan(x) ((x) | 0x0008000000000000ULL) +#define float32_snan_to_qnan(x) ((x) | 0x00400000) + /*****************************************************************************/ /* Floating point operations helpers */ uint64_t helper_float32_to_float64(CPUPPCState *env, uint32_t arg) @@ -926,14 +929,16 @@ uint64_t helper_fsqrt(CPUPPCState *env, uint64_t arg) farg.ll = arg; - if (unlikely(float64_is_neg(farg.d) && !float64_is_zero(farg.d))) { - /* Square root of a negative nonzero number */ - farg.ll = fload_invalid_op_excp(env, POWERPC_EXCP_FP_VXSQRT, 1); - } else { + if (unlikely(float64_is_any_nan(farg.d))) { if (unlikely(float64_is_signaling_nan(farg.d))) { - /* sNaN square root */ + /* sNaN reciprocal square root */ fload_invalid_op_excp(env, POWERPC_EXCP_FP_VXSNAN, 1); + farg.ll = float64_snan_to_qnan(farg.ll); } + } else if (unlikely(float64_is_neg(farg.d) && !float64_is_zero(farg.d))) { + /* Square root of a negative nonzero number */ + farg.ll = fload_invalid_op_excp(env, POWERPC_EXCP_FP_VXSQRT, 1); + } else { farg.d = float64_sqrt(farg.d, &env->fp_status); } return farg.ll; @@ -980,17 +985,20 @@ uint64_t helper_frsqrte(CPUPPCState *env, uint64_t arg) farg.ll = arg; - if (unlikely(float64_is_neg(farg.d) && !float64_is_zero(farg.d))) { - /* Reciprocal square root of a negative nonzero number */ - farg.ll = fload_invalid_op_excp(env, POWERPC_EXCP_FP_VXSQRT, 1); - } else { + if (unlikely(float64_is_any_nan(farg.d))) { if (unlikely(float64_is_signaling_nan(farg.d))) { /* sNaN reciprocal square root */ fload_invalid_op_excp(env, POWERPC_EXCP_FP_VXSNAN, 1); + farg.ll = float64_snan_to_qnan(farg.ll); } + } else if (unlikely(float64_is_neg(farg.d) && !float64_is_zero(farg.d))) { + /* Reciprocal square root of a negative nonzero number */ + farg.ll = fload_invalid_op_excp(env, POWERPC_EXCP_FP_VXSQRT, 1); + } else { farg.d = float64_sqrt(farg.d, &env->fp_status); farg.d = float64_div(float64_one, farg.d, &env->fp_status); } + return farg.ll; } @@ -2388,9 +2396,6 @@ void helper_##op(CPUPPCState *env, uint32_t opcode) \ VSX_SCALAR_CMP(xscmpodp, 1) VSX_SCALAR_CMP(xscmpudp, 0) -#define float64_snan_to_qnan(x) ((x) | 0x0008000000000000ULL) -#define float32_snan_to_qnan(x) ((x) | 0x00400000) - /* VSX_MAX_MIN - VSX floating point maximum/minimum * name - instruction mnemonic * op - operation (max or min) -- 1.7.1