From 3ecec4c0429f65de1822b881ea732689cf647254 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?V=C3=ADctor=20Colombo?= Date: Tue, 6 Sep 2022 09:55:19 -0300 Subject: [PATCH] target/ppc: Set result to QNaN for DENBCD when VXCVI occurs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit According to the ISA, for instruction DENBCD: "If an invalid BCD digit or sign code is detected in the source operand, an invalid-operation exception (VXCVI) occurs." In the Invalid Operation Exception section, there is the situation: "When Invalid Operation Exception is disabled (VE=0) and Invalid Operation occurs (...) If the operation is an (...) or format the target FPR is set to a Quiet NaN". This was not being done in QEMU. This patch sets the result to QNaN when the instruction DENBCD causes an Invalid Operation Exception. Signed-off-by: Víctor Colombo Reviewed-by: Daniel Henrique Barboza Message-Id: <20220906125523.38765-5-victor.colombo@eldorado.org.br> Signed-off-by: Daniel Henrique Barboza --- target/ppc/dfp_helper.c | 26 ++++++++++++++++++++++++-- 1 file changed, 24 insertions(+), 2 deletions(-) diff --git a/target/ppc/dfp_helper.c b/target/ppc/dfp_helper.c index be7aa5357a..cc024316d5 100644 --- a/target/ppc/dfp_helper.c +++ b/target/ppc/dfp_helper.c @@ -1147,6 +1147,26 @@ static inline uint8_t dfp_get_bcd_digit_128(ppc_vsr_t *t, unsigned n) return t->VsrD((n & 0x10) ? 0 : 1) >> ((n << 2) & 63) & 15; } +static inline void dfp_invalid_op_vxcvi_64(struct PPC_DFP *dfp) +{ + /* TODO: fpscr is incorrectly not being saved to env */ + dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXCVI, FPSCR_VE); + if ((dfp->env->fpscr & FP_VE) == 0) { + dfp->vt.VsrD(1) = 0x7c00000000000000; /* QNaN */ + } +} + + +static inline void dfp_invalid_op_vxcvi_128(struct PPC_DFP *dfp) +{ + /* TODO: fpscr is incorrectly not being saved to env */ + dfp_set_FPSCR_flag(dfp, FP_VX | FP_VXCVI, FPSCR_VE); + if ((dfp->env->fpscr & FP_VE) == 0) { + dfp->vt.VsrD(0) = 0x7c00000000000000; /* QNaN */ + dfp->vt.VsrD(1) = 0x0; + } +} + #define DFP_HELPER_ENBCD(op, size) \ void helper_##op(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *b, \ uint32_t s) \ @@ -1173,7 +1193,8 @@ void helper_##op(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *b, \ sgn = 0; \ break; \ default: \ - dfp_set_FPSCR_flag(&dfp, FP_VX | FP_VXCVI, FPSCR_VE); \ + dfp_invalid_op_vxcvi_##size(&dfp); \ + set_dfp##size(t, &dfp.vt); \ return; \ } \ } \ @@ -1183,7 +1204,8 @@ void helper_##op(CPUPPCState *env, ppc_fprp_t *t, ppc_fprp_t *b, \ digits[(size) / 4 - n] = dfp_get_bcd_digit_##size(&dfp.vb, \ offset++); \ if (digits[(size) / 4 - n] > 10) { \ - dfp_set_FPSCR_flag(&dfp, FP_VX | FP_VXCVI, FPSCR_VE); \ + dfp_invalid_op_vxcvi_##size(&dfp); \ + set_dfp##size(t, &dfp.vt); \ return; \ } else { \ nonzero |= (digits[(size) / 4 - n] > 0); \