From patchwork Thu Nov 18 13:25:00 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lucas Mateus Martins Araujo e Castro X-Patchwork-Id: 12627007 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1EC29C433EF for ; Thu, 18 Nov 2021 13:32:50 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CCD2A6140A for ; Thu, 18 Nov 2021 13:32:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org CCD2A6140A Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=eldorado.org.br Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:49770 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mnhWz-0004m2-0M for qemu-devel@archiver.kernel.org; Thu, 18 Nov 2021 08:32:49 -0500 Received: from eggs.gnu.org ([209.51.188.92]:54110) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mnhPk-00013f-KS; Thu, 18 Nov 2021 08:25:22 -0500 Received: from [201.28.113.2] (port=22122 helo=outlook.eldorado.org.br) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mnhPj-0000gy-1f; Thu, 18 Nov 2021 08:25:20 -0500 Received: from power9a ([10.10.71.235]) by outlook.eldorado.org.br with Microsoft SMTPSVC(8.5.9600.16384); Thu, 18 Nov 2021 10:25:09 -0300 Received: from eldorado.org.br (unknown [10.10.71.29]) by power9a (Postfix) with ESMTP id EB21D800B36; Thu, 18 Nov 2021 10:25:08 -0300 (-03) From: "Lucas Mateus Castro (alqotel)" To: qemu-devel@nongnu.org, qemu-ppc@nongnu.org Subject: [PATCH v2 1/3] target/ppc: Fixed call to deferred exception Date: Thu, 18 Nov 2021 10:25:00 -0300 Message-Id: <20211118132502.984059-2-lucas.araujo@eldorado.org.br> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20211118132502.984059-1-lucas.araujo@eldorado.org.br> References: <20211118132502.984059-1-lucas.araujo@eldorado.org.br> MIME-Version: 1.0 X-OriginalArrivalTime: 18 Nov 2021 13:25:09.0081 (UTC) FILETIME=[B5440490:01D7DC7F] X-Host-Lookup-Failed: Reverse DNS lookup failed for 201.28.113.2 (failed) Received-SPF: pass client-ip=201.28.113.2; envelope-from=lucas.araujo@eldorado.org.br; helo=outlook.eldorado.org.br X-Spam_score_int: -10 X-Spam_score: -1.1 X-Spam_bar: - X-Spam_report: (-1.1 / 5.0 requ) BAYES_00=-1.9, PDS_HP_HELO_NORDNS=0.001, RDNS_NONE=0.793, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: richard.henderson@linaro.org, danielhb413@gmail.com, mark.cave-ayland@ilande.co.uk, "Lucas Mateus Castro \(alqotel\)" , pc@us.ibm.com, david@gibson.dropbear.id.au, matheus.ferst@eldorado.org.br, clg@kaod.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" mtfsf, mtfsfi and mtfsb1 instructions call helper_float_check_status after updating the value of FPSCR, but helper_float_check_status checks fp_status and fp_status isn't updated based on FPSCR and since the value of fp_status is reset earlier in the instruction, it's always 0. Because of this helper_float_check_status would change the FI bit to 0 as this bit checks if the last operation was inexact and float_flag_inexact is always 0. These instructions also don't throw exceptions correctly since helper_float_check_status throw exceptions based on fp_status. This commit created a new helper, helper_fpscr_check_status that checks FPSCR value instead of fp_status and checks for a larger variety of exceptions than do_float_check_status. Since fp_status isn't used, gen_reset_fpstatus() was removed. The hardware used to compare QEMU's behavior to was a Power9. Signed-off-by: Lucas Mateus Castro (alqotel) --- target/ppc/fpu_helper.c | 41 ++++++++++++++++++++++++++++++ target/ppc/helper.h | 1 + target/ppc/translate/fp-impl.c.inc | 9 +++---- 3 files changed, 45 insertions(+), 6 deletions(-) diff --git a/target/ppc/fpu_helper.c b/target/ppc/fpu_helper.c index c4896cecc8..f086cb503f 100644 --- a/target/ppc/fpu_helper.c +++ b/target/ppc/fpu_helper.c @@ -414,6 +414,47 @@ void helper_store_fpscr(CPUPPCState *env, uint64_t val, uint32_t nibbles) ppc_store_fpscr(env, val); } +void helper_fpscr_check_status(CPUPPCState *env) +{ + CPUState *cs = env_cpu(env); + target_ulong fpscr = env->fpscr; + int error = 0; + + if ((fpscr & FP_VXSOFT) && (fpscr_ve != 0)) { + error = POWERPC_EXCP_FP_VXSOFT; + } else if ((fpscr & FP_OX) && (fpscr & FP_OE)) { + error = POWERPC_EXCP_FP_OX; + } else if ((fpscr & FP_UX) && (fpscr & FP_UE)) { + error = POWERPC_EXCP_FP_UX; + } else if ((fpscr & FP_XX) && (fpscr & FP_XE)) { + error = POWERPC_EXCP_FP_XX; + } else if ((fpscr & FP_ZX) && (fpscr & FP_ZE)) { + error = POWERPC_EXCP_FP_ZX; + } else if ((fpscr & FP_VXSNAN) && (fpscr_ve != 0)) { + error = POWERPC_EXCP_FP_VXSNAN; + } else if ((fpscr & FP_VXISI) && (fpscr_ve != 0)) { + error = POWERPC_EXCP_FP_VXISI; + } else if ((fpscr & FP_VXIDI) && (fpscr_ve != 0)) { + error = POWERPC_EXCP_FP_VXIDI; + } else if ((fpscr & FP_VXZDZ) && (fpscr_ve != 0)) { + error = POWERPC_EXCP_FP_VXZDZ; + } else if ((fpscr & FP_VXIMZ) && (fpscr_ve != 0)) { + error = POWERPC_EXCP_FP_VXIMZ; + } else if ((fpscr & FP_VXVC) && (fpscr_ve != 0)) { + error = POWERPC_EXCP_FP_VXVC; + } + + if (error) { + cs->exception_index = POWERPC_EXCP_PROGRAM; + env->error_code = error | POWERPC_EXCP_FP; + /* Deferred floating-point exception after target FPSCR update */ + if (fp_exceptions_enabled(env)) { + raise_exception_err_ra(env, cs->exception_index, + env->error_code, GETPC()); + } + } +} + static void do_float_check_status(CPUPPCState *env, uintptr_t raddr) { CPUState *cs = env_cpu(env); diff --git a/target/ppc/helper.h b/target/ppc/helper.h index 627811cefc..632a81c676 100644 --- a/target/ppc/helper.h +++ b/target/ppc/helper.h @@ -63,6 +63,7 @@ DEF_HELPER_FLAGS_1(cntlzw32, TCG_CALL_NO_RWG_SE, i32, i32) DEF_HELPER_FLAGS_2(brinc, TCG_CALL_NO_RWG_SE, tl, tl, tl) DEF_HELPER_1(float_check_status, void, env) +DEF_HELPER_1(fpscr_check_status, void, env) DEF_HELPER_1(reset_fpstatus, void, env) DEF_HELPER_2(compute_fprf_float64, void, env, i64) DEF_HELPER_3(store_fpscr, void, env, i64, i32) diff --git a/target/ppc/translate/fp-impl.c.inc b/target/ppc/translate/fp-impl.c.inc index d1dbb1b96b..ca195fd9d2 100644 --- a/target/ppc/translate/fp-impl.c.inc +++ b/target/ppc/translate/fp-impl.c.inc @@ -769,7 +769,6 @@ static void gen_mtfsb1(DisasContext *ctx) return; } crb = 31 - crbD(ctx->opcode); - gen_reset_fpstatus(); /* XXX: we pretend we can only do IEEE floating-point computations */ if (likely(crb != FPSCR_FEX && crb != FPSCR_VX && crb != FPSCR_NI)) { TCGv_i32 t0; @@ -782,7 +781,7 @@ static void gen_mtfsb1(DisasContext *ctx) tcg_gen_shri_i32(cpu_crf[1], cpu_crf[1], FPSCR_OX); } /* We can raise a deferred exception */ - gen_helper_float_check_status(cpu_env); + gen_helper_fpscr_check_status(cpu_env); } /* mtfsf */ @@ -803,7 +802,6 @@ static void gen_mtfsf(DisasContext *ctx) gen_inval_exception(ctx, POWERPC_EXCP_INVAL_INVAL); return; } - gen_reset_fpstatus(); if (l) { t0 = tcg_const_i32((ctx->insns_flags2 & PPC2_ISA205) ? 0xffff : 0xff); } else { @@ -818,7 +816,7 @@ static void gen_mtfsf(DisasContext *ctx) tcg_gen_shri_i32(cpu_crf[1], cpu_crf[1], FPSCR_OX); } /* We can raise a deferred exception */ - gen_helper_float_check_status(cpu_env); + gen_helper_fpscr_check_status(cpu_env); tcg_temp_free_i64(t1); } @@ -840,7 +838,6 @@ static void gen_mtfsfi(DisasContext *ctx) return; } sh = (8 * w) + 7 - bf; - gen_reset_fpstatus(); t0 = tcg_const_i64(((uint64_t)FPIMM(ctx->opcode)) << (4 * sh)); t1 = tcg_const_i32(1 << sh); gen_helper_store_fpscr(cpu_env, t0, t1); @@ -851,7 +848,7 @@ static void gen_mtfsfi(DisasContext *ctx) tcg_gen_shri_i32(cpu_crf[1], cpu_crf[1], FPSCR_OX); } /* We can raise a deferred exception */ - gen_helper_float_check_status(cpu_env); + gen_helper_fpscr_check_status(cpu_env); } static void gen_qemu_ld32fs(DisasContext *ctx, TCGv_i64 dest, TCGv addr) From patchwork Thu Nov 18 13:25:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lucas Mateus Martins Araujo e Castro X-Patchwork-Id: 12627011 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B5E99C433EF for ; Thu, 18 Nov 2021 13:37:52 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 432EC617E5 for ; Thu, 18 Nov 2021 13:37:52 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 432EC617E5 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=eldorado.org.br Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:55500 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mnhbr-0000Gp-7B for qemu-devel@archiver.kernel.org; Thu, 18 Nov 2021 08:37:51 -0500 Received: from eggs.gnu.org ([209.51.188.92]:54136) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mnhPq-00015Q-F1; Thu, 18 Nov 2021 08:25:26 -0500 Received: from [201.28.113.2] (port=22122 helo=outlook.eldorado.org.br) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mnhPl-0000gy-OG; Thu, 18 Nov 2021 08:25:22 -0500 Received: from power9a ([10.10.71.235]) by outlook.eldorado.org.br with Microsoft SMTPSVC(8.5.9600.16384); Thu, 18 Nov 2021 10:25:10 -0300 Received: from eldorado.org.br (unknown [10.10.71.29]) by power9a (Postfix) with ESMTP id E0EF0800B36; Thu, 18 Nov 2021 10:25:09 -0300 (-03) From: "Lucas Mateus Castro (alqotel)" To: qemu-devel@nongnu.org, qemu-ppc@nongnu.org Subject: [PATCH v2 2/3] target/ppc: ppc_store_fpscr doesn't update bit 52 Date: Thu, 18 Nov 2021 10:25:01 -0300 Message-Id: <20211118132502.984059-3-lucas.araujo@eldorado.org.br> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20211118132502.984059-1-lucas.araujo@eldorado.org.br> References: <20211118132502.984059-1-lucas.araujo@eldorado.org.br> MIME-Version: 1.0 X-OriginalArrivalTime: 18 Nov 2021 13:25:10.0065 (UTC) FILETIME=[B5DA2A10:01D7DC7F] X-Host-Lookup-Failed: Reverse DNS lookup failed for 201.28.113.2 (failed) Received-SPF: pass client-ip=201.28.113.2; envelope-from=lucas.araujo@eldorado.org.br; helo=outlook.eldorado.org.br X-Spam_score_int: -10 X-Spam_score: -1.1 X-Spam_bar: - X-Spam_report: (-1.1 / 5.0 requ) BAYES_00=-1.9, PDS_HP_HELO_NORDNS=0.001, RDNS_NONE=0.793, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: richard.henderson@linaro.org, danielhb413@gmail.com, mark.cave-ayland@ilande.co.uk, "Lucas Mateus Castro \(alqotel\)" , pc@us.ibm.com, david@gibson.dropbear.id.au, matheus.ferst@eldorado.org.br, clg@kaod.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" This commit fixes the difference reported in the bug in the reserved bit 52, it does this by adding this bit to the mask of bits to not be directly altered in the ppc_store_fpscr function (the hardware used to compare to QEMU was a Power9). Although this is a difference reported in the bug, since it's a reserved bit it may be a "don't care" case, as put in the bug report. Looking at the ISA it doesn't explicitly mentions this bit can't be set, like it does for FEX and VX, so I'm unsure if this is necessary. Resolves: https://gitlab.com/qemu-project/qemu/-/issues/266 Signed-off-by: Lucas Mateus Castro (alqotel) --- target/ppc/cpu.c | 2 +- target/ppc/cpu.h | 3 +++ 2 files changed, 4 insertions(+), 1 deletion(-) diff --git a/target/ppc/cpu.c b/target/ppc/cpu.c index f933d9f2bd..d7b42bae52 100644 --- a/target/ppc/cpu.c +++ b/target/ppc/cpu.c @@ -112,7 +112,7 @@ static inline void fpscr_set_rounding_mode(CPUPPCState *env) void ppc_store_fpscr(CPUPPCState *env, target_ulong val) { - val &= ~(FP_VX | FP_FEX); + val &= FPSCR_MTFS_MASK; if (val & FPSCR_IX) { val |= FP_VX; } diff --git a/target/ppc/cpu.h b/target/ppc/cpu.h index e946da5f3a..53463092ab 100644 --- a/target/ppc/cpu.h +++ b/target/ppc/cpu.h @@ -759,6 +759,9 @@ enum { FP_VXZDZ | FP_VXIMZ | FP_VXVC | FP_VXSOFT | \ FP_VXSQRT | FP_VXCVI) +/* FPSCR bits that can be set by mtfsf, mtfsfi and mtfsb1 */ +#define FPSCR_MTFS_MASK (~((1ull << 11) | FP_VX | FP_FEX)) + /*****************************************************************************/ /* Vector status and control register */ #define VSCR_NJ 16 /* Vector non-java */ From patchwork Thu Nov 18 13:25:02 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Lucas Mateus Martins Araujo e Castro X-Patchwork-Id: 12627033 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6A632C433F5 for ; Thu, 18 Nov 2021 13:40:12 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 0B83F617E3 for ; Thu, 18 Nov 2021 13:40:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 0B83F617E3 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=eldorado.org.br Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=nongnu.org Received: from localhost ([::1]:57714 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mnhe6-0001h9-Sx for qemu-devel@archiver.kernel.org; Thu, 18 Nov 2021 08:40:10 -0500 Received: from eggs.gnu.org ([209.51.188.92]:54152) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1mnhPt-0001BU-Vz; Thu, 18 Nov 2021 08:25:30 -0500 Received: from [201.28.113.2] (port=22122 helo=outlook.eldorado.org.br) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1mnhPs-0000gy-2E; Thu, 18 Nov 2021 08:25:29 -0500 Received: from power9a ([10.10.71.235]) by outlook.eldorado.org.br with Microsoft SMTPSVC(8.5.9600.16384); Thu, 18 Nov 2021 10:25:10 -0300 Received: from eldorado.org.br (unknown [10.10.71.29]) by power9a (Postfix) with ESMTP id C1B3E800B36; Thu, 18 Nov 2021 10:25:10 -0300 (-03) From: "Lucas Mateus Castro (alqotel)" To: qemu-devel@nongnu.org, qemu-ppc@nongnu.org Subject: [PATCH v2 3/3] test/tcg/ppc64le: test mtfsf Date: Thu, 18 Nov 2021 10:25:02 -0300 Message-Id: <20211118132502.984059-4-lucas.araujo@eldorado.org.br> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20211118132502.984059-1-lucas.araujo@eldorado.org.br> References: <20211118132502.984059-1-lucas.araujo@eldorado.org.br> MIME-Version: 1.0 X-OriginalArrivalTime: 18 Nov 2021 13:25:10.0910 (UTC) FILETIME=[B65B19E0:01D7DC7F] X-Host-Lookup-Failed: Reverse DNS lookup failed for 201.28.113.2 (failed) Received-SPF: pass client-ip=201.28.113.2; envelope-from=lucas.araujo@eldorado.org.br; helo=outlook.eldorado.org.br X-Spam_score_int: -10 X-Spam_score: -1.1 X-Spam_bar: - X-Spam_report: (-1.1 / 5.0 requ) BAYES_00=-1.9, PDS_HP_HELO_NORDNS=0.001, RDNS_NONE=0.793, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: richard.henderson@linaro.org, danielhb413@gmail.com, mark.cave-ayland@ilande.co.uk, "Lucas Mateus Castro \(alqotel\)" , pc@us.ibm.com, david@gibson.dropbear.id.au, matheus.ferst@eldorado.org.br, clg@kaod.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Added tests for the mtfsf to check if FI bit of FPSCR is being set and if exception calls are being made correctly. Signed-off-by: Lucas Mateus Castro (alqotel) Reviewed-by: Richard Henderson --- tests/tcg/ppc64/Makefile.target | 1 + tests/tcg/ppc64le/Makefile.target | 1 + tests/tcg/ppc64le/mtfsf.c | 56 +++++++++++++++++++++++++++++++ 3 files changed, 58 insertions(+) create mode 100644 tests/tcg/ppc64le/mtfsf.c diff --git a/tests/tcg/ppc64/Makefile.target b/tests/tcg/ppc64/Makefile.target index 6ab7934fdf..8f4c7ac4ed 100644 --- a/tests/tcg/ppc64/Makefile.target +++ b/tests/tcg/ppc64/Makefile.target @@ -11,6 +11,7 @@ endif bcdsub: CFLAGS += -mpower8-vector PPC64_TESTS += byte_reverse +PPC64_TESTS += mtfsf ifneq ($(DOCKER_IMAGE)$(CROSS_CC_HAS_POWER10),) run-byte_reverse: QEMU_OPTS+=-cpu POWER10 run-plugin-byte_reverse-with-%: QEMU_OPTS+=-cpu POWER10 diff --git a/tests/tcg/ppc64le/Makefile.target b/tests/tcg/ppc64le/Makefile.target index 5e65b1590d..b8cd9bf73a 100644 --- a/tests/tcg/ppc64le/Makefile.target +++ b/tests/tcg/ppc64le/Makefile.target @@ -10,6 +10,7 @@ endif bcdsub: CFLAGS += -mpower8-vector PPC64LE_TESTS += byte_reverse +PPC64LE_TESTS += mtfsf ifneq ($(DOCKER_IMAGE)$(CROSS_CC_HAS_POWER10),) run-byte_reverse: QEMU_OPTS+=-cpu POWER10 run-plugin-byte_reverse-with-%: QEMU_OPTS+=-cpu POWER10 diff --git a/tests/tcg/ppc64le/mtfsf.c b/tests/tcg/ppc64le/mtfsf.c new file mode 100644 index 0000000000..9b3290d94c --- /dev/null +++ b/tests/tcg/ppc64le/mtfsf.c @@ -0,0 +1,56 @@ +#include +#include +#include +#include + +#define FPSCR_VE 7 /* Floating-point invalid operation exception enable */ +#define FPSCR_VXSOFT 10 /* Floating-point invalid operation exception (soft) */ +#define FPSCR_FI 17 /* Floating-point fraction inexact */ + +#define FP_VE (1ull << FPSCR_VE) +#define FP_VXSOFT (1ull << FPSCR_VXSOFT) +#define FP_FI (1ull << FPSCR_FI) + +void sigfpe_handler(int sig, siginfo_t *si, void *ucontext) +{ + exit(0); +} + +int main(void) +{ + union { + double d; + long long ll; + } fpscr; + + struct sigaction sa = { + .sa_sigaction = sigfpe_handler, + .sa_flags = SA_SIGINFO + }; + + /* + * Enable the MSR bits F0 and F1 to enable exceptions. + * This shouldn't be needed in linux-user as these bits are enabled by + * default, but this allows to execute either in a VM or a real machine + * to compare the behaviors. + */ + prctl(PR_SET_FPEXC, PR_FP_EXC_PRECISE); + + /* First test if the FI bit is being set correctly */ + fpscr.ll = FP_FI; + __builtin_mtfsf(0b11111111, fpscr.d); + fpscr.d = __builtin_mffs(); + assert((fpscr.ll & FP_FI) != 0); + + /* Then test if the deferred exception is being called correctly */ + sigaction(SIGFPE, &sa, NULL); + + /* + * Although the VXSOFT exception has been chosen, based on test in a Power9 + * any combination of exception bit + its enabling bit should work. + */ + fpscr.ll = FP_VE | FP_VXSOFT; + __builtin_mtfsf(0b11111111, fpscr.d); + + return 1; +}