From 892d0f4afb2614603157600e9d5d0aaa878b5d31 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Thu, 21 Apr 2022 08:16:32 -0700 Subject: linux-user/nios2: Hoist pc advance to the top of EXCP_TRAP Note that this advance *should* be done by the translator, as that's the pc value that's supposed to be generated by hardware. However, that's a much larger change across sysemu as well. In the meantime, produce the correct PC for any signals raised by the trap instruction. Note the special case of TRAP_BRKPT, which itself is special cased within the kernel. Reviewed-by: Peter Maydell Signed-off-by: Richard Henderson Message-Id: <20220421151735.31996-2-richard.henderson@linaro.org> --- linux-user/nios2/cpu_loop.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'linux-user/nios2') diff --git a/linux-user/nios2/cpu_loop.c b/linux-user/nios2/cpu_loop.c index 1e93ef34e6..2e9296750d 100644 --- a/linux-user/nios2/cpu_loop.c +++ b/linux-user/nios2/cpu_loop.c @@ -40,6 +40,12 @@ void cpu_loop(CPUNios2State *env) break; case EXCP_TRAP: + /* + * TODO: This advance should be done in the translator, as + * hardware produces an advanced pc as part of all exceptions. + */ + env->regs[R_PC] += 4; + switch (env->error_code) { case 0: qemu_log_mask(CPU_LOG_INT, "\nSyscall\n"); @@ -56,7 +62,6 @@ void cpu_loop(CPUNios2State *env) env->regs[2] = abs(ret); /* Return value is 0..4096 */ env->regs[7] = ret > 0xfffff000u; - env->regs[R_PC] += 4; break; case 1: @@ -69,6 +74,8 @@ void cpu_loop(CPUNios2State *env) break; case 31: qemu_log_mask(CPU_LOG_INT, "\nTrap 31\n"); + /* Match kernel's breakpoint_c(). */ + env->regs[R_PC] -= 4; force_sig_fault(TARGET_SIGTRAP, TARGET_TRAP_BRKPT, env->regs[R_PC]); break; default: @@ -99,7 +106,6 @@ void cpu_loop(CPUNios2State *env) o = env->regs[5]; n = env->regs[6]; env->regs[2] = qatomic_cmpxchg(h, o, n) - o; - env->regs[R_PC] += 4; } break; } -- cgit v1.2.3