From 5bde14078d181439a1170094d7774372242ab739 Mon Sep 17 00:00:00 2001 From: Pavel Dovgalyuk Date: Wed, 17 Sep 2014 12:05:19 +0400 Subject: [PATCH] target-i386: update fp status fix This patch introduces cpu_set_fpuc() function, which changes fpuc field of the CPU state and calls update_fp_status() function. These calls update status of softfloat library and prevent bugs caused by non-coherent rounding settings of the FPU and softfloat. v2 changes: * Added missed calls and intoduced setter function (as suggested by TeLeMan) Reviewed-by: TeLeMan Signed-off-by: Paolo Bonzini Signed-off-by: Pavel Dovgalyuk --- target-i386/cpu.c | 2 +- target-i386/cpu.h | 2 ++ target-i386/fpu_helper.c | 21 +++++++++++++-------- target-i386/gdbstub.c | 2 +- target-i386/machine.c | 2 +- 5 files changed, 18 insertions(+), 11 deletions(-) diff --git a/target-i386/cpu.c b/target-i386/cpu.c index 90d0a05eb1..25e74b08d9 100644 --- a/target-i386/cpu.c +++ b/target-i386/cpu.c @@ -2580,7 +2580,7 @@ static void x86_cpu_reset(CPUState *s) for (i = 0; i < 8; i++) { env->fptags[i] = 1; } - env->fpuc = 0x37f; + cpu_set_fpuc(env, 0x37f); env->mxcsr = 0x1f80; env->xstate_bv = XSTATE_FP | XSTATE_SSE; diff --git a/target-i386/cpu.h b/target-i386/cpu.h index 71b505f56c..2968749578 100644 --- a/target-i386/cpu.h +++ b/target-i386/cpu.h @@ -1251,6 +1251,7 @@ void QEMU_NORETURN raise_interrupt(CPUX86State *nenv, int intno, int is_int, /* cc_helper.c */ extern const uint8_t parity_table[256]; uint32_t cpu_cc_compute_all(CPUX86State *env1, int op); +void update_fp_status(CPUX86State *env); static inline uint32_t cpu_compute_eflags(CPUX86State *env) { @@ -1286,6 +1287,7 @@ static inline void cpu_load_efer(CPUX86State *env, uint64_t val) /* fpu_helper.c */ void cpu_set_mxcsr(CPUX86State *env, uint32_t val); +void cpu_set_fpuc(CPUX86State *env, uint16_t val); /* svm_helper.c */ void cpu_svm_check_intercept_param(CPUX86State *env1, uint32_t type, diff --git a/target-i386/fpu_helper.c b/target-i386/fpu_helper.c index 1b2900d5d2..1d4eee3974 100644 --- a/target-i386/fpu_helper.c +++ b/target-i386/fpu_helper.c @@ -537,7 +537,7 @@ uint32_t helper_fnstcw(CPUX86State *env) return env->fpuc; } -static void update_fp_status(CPUX86State *env) +void update_fp_status(CPUX86State *env) { int rnd_type; @@ -575,8 +575,7 @@ static void update_fp_status(CPUX86State *env) void helper_fldcw(CPUX86State *env, uint32_t val) { - env->fpuc = val; - update_fp_status(env); + cpu_set_fpuc(env, val); } void helper_fclex(CPUX86State *env) @@ -595,7 +594,7 @@ void helper_fninit(CPUX86State *env) { env->fpus = 0; env->fpstt = 0; - env->fpuc = 0x37f; + cpu_set_fpuc(env, 0x37f); env->fptags[0] = 1; env->fptags[1] = 1; env->fptags[2] = 1; @@ -1013,11 +1012,11 @@ void helper_fldenv(CPUX86State *env, target_ulong ptr, int data32) int i, fpus, fptag; if (data32) { - env->fpuc = cpu_lduw_data(env, ptr); + cpu_set_fpuc(env, cpu_lduw_data(env, ptr)); fpus = cpu_lduw_data(env, ptr + 4); fptag = cpu_lduw_data(env, ptr + 8); } else { - env->fpuc = cpu_lduw_data(env, ptr); + cpu_set_fpuc(env, cpu_lduw_data(env, ptr)); fpus = cpu_lduw_data(env, ptr + 2); fptag = cpu_lduw_data(env, ptr + 4); } @@ -1046,7 +1045,7 @@ void helper_fsave(CPUX86State *env, target_ulong ptr, int data32) /* fninit */ env->fpus = 0; env->fpstt = 0; - env->fpuc = 0x37f; + cpu_set_fpuc(env, 0x37f); env->fptags[0] = 1; env->fptags[1] = 1; env->fptags[2] = 1; @@ -1157,7 +1156,7 @@ void helper_fxrstor(CPUX86State *env, target_ulong ptr, int data64) raise_exception(env, EXCP0D_GPF); } - env->fpuc = cpu_lduw_data(env, ptr); + cpu_set_fpuc(env, cpu_lduw_data(env, ptr)); fpus = cpu_lduw_data(env, ptr + 2); fptag = cpu_lduw_data(env, ptr + 4); env->fpstt = (fpus >> 11) & 7; @@ -1257,6 +1256,12 @@ void cpu_set_mxcsr(CPUX86State *env, uint32_t mxcsr) set_flush_to_zero((mxcsr & SSE_FZ) ? 1 : 0, &env->fp_status); } +void cpu_set_fpuc(CPUX86State *env, uint16_t val) +{ + env->fpuc = val; + update_fp_status(env); +} + void helper_ldmxcsr(CPUX86State *env, uint32_t val) { cpu_set_mxcsr(env, val); diff --git a/target-i386/gdbstub.c b/target-i386/gdbstub.c index 19fe9adc3f..ff99cfb007 100644 --- a/target-i386/gdbstub.c +++ b/target-i386/gdbstub.c @@ -203,7 +203,7 @@ int x86_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n) return x86_cpu_gdb_load_seg(cpu, R_GS, mem_buf); case IDX_FP_REGS + 8: - env->fpuc = ldl_p(mem_buf); + cpu_set_fpuc(env, ldl_p(mem_buf)); return 4; case IDX_FP_REGS + 9: tmp = ldl_p(mem_buf); diff --git a/target-i386/machine.c b/target-i386/machine.c index fb890654b1..0dd49f0005 100644 --- a/target-i386/machine.c +++ b/target-i386/machine.c @@ -315,13 +315,13 @@ static int cpu_post_load(void *opaque, int version_id) env->hflags &= ~HF_CPL_MASK; env->hflags |= (env->segs[R_SS].flags >> DESC_DPL_SHIFT) & HF_CPL_MASK; - /* XXX: restore FPU round state */ env->fpstt = (env->fpus_vmstate >> 11) & 7; env->fpus = env->fpus_vmstate & ~0x3800; env->fptag_vmstate ^= 0xff; for(i = 0; i < 8; i++) { env->fptags[i] = (env->fptag_vmstate >> i) & 1; } + update_fp_status(env); cpu_breakpoint_remove_all(cs, BP_CPU); cpu_watchpoint_remove_all(cs, BP_CPU); -- 2.39.2