From fe43ba9721f36e47e09779682c3525659c6818f0 Mon Sep 17 00:00:00 2001 From: "Bruno Larsen (billionai)" Date: Thu, 27 May 2021 13:35:22 -0300 Subject: target/ppc: overhauled and moved logic of storing fpscr Followed the suggested overhaul to store_fpscr logic, and moved it to cpu.c where it can be accessed in !TCG builds. The overhaul was suggested because storing a value to fpscr should never raise an exception, so we could remove all the mess that happened with POWERPC_EXCP_FP. We also moved fpscr_set_rounding_mode into cpu.c as it could now be moved there, and it is needed when a value for the fpscr is being stored directly. Suggested-by: Richard Henderson Signed-off-by: Bruno Larsen (billionai) Reviewed-by: Richard Henderson Message-Id: <20210527163522.23019-1-bruno.larsen@eldorado.org.br> Signed-off-by: David Gibson --- target/ppc/cpu.c | 43 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 43 insertions(+) (limited to 'target/ppc/cpu.c') diff --git a/target/ppc/cpu.c b/target/ppc/cpu.c index c8e87e3..19d67b5 100644 --- a/target/ppc/cpu.c +++ b/target/ppc/cpu.c @@ -25,6 +25,7 @@ #include "fpu/softfloat-helpers.h" #include "mmu-hash64.h" #include "helper_regs.h" +#include "sysemu/tcg.h" target_ulong cpu_read_xer(CPUPPCState *env) { @@ -109,3 +110,45 @@ void ppc_store_lpcr(PowerPCCPU *cpu, target_ulong val) /* The gtse bit affects hflags */ hreg_compute_hflags(env); } + +static inline void fpscr_set_rounding_mode(CPUPPCState *env) +{ + int rnd_type; + + /* Set rounding mode */ + switch (fpscr_rn) { + case 0: + /* Best approximation (round to nearest) */ + rnd_type = float_round_nearest_even; + break; + case 1: + /* Smaller magnitude (round toward zero) */ + rnd_type = float_round_to_zero; + break; + case 2: + /* Round toward +infinite */ + rnd_type = float_round_up; + break; + default: + case 3: + /* Round toward -infinite */ + rnd_type = float_round_down; + break; + } + set_float_rounding_mode(rnd_type, &env->fp_status); +} + +void ppc_store_fpscr(CPUPPCState *env, target_ulong val) +{ + val &= ~(FP_VX | FP_FEX); + if (val & FPSCR_IX) { + val |= FP_VX; + } + if ((val >> FPSCR_XX) & (val >> FPSCR_XE) & 0x1f) { + val |= FP_FEX; + } + env->fpscr = val; + if (tcg_enabled()) { + fpscr_set_rounding_mode(env); + } +} -- cgit v1.1