From: Michael Davidsaver <mdavidsa...@gmail.com> The CCR.STACKALIGN bit controls whether the CPU is supposed to force 8-alignment of the stack pointer on entry to the exception handler.
Signed-off-by: Michael Davidsaver <mdavidsa...@gmail.com> Message-id: 1485285380-10565-6-git-send-email-peter.mayd...@linaro.org [PMM: commit message and comment tweaks] Signed-off-by: Peter Maydell <peter.mayd...@linaro.org> --- target/arm/helper.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/target/arm/helper.c b/target/arm/helper.c index ce7e43b..7dc30f5 100644 --- a/target/arm/helper.c +++ b/target/arm/helper.c @@ -6110,10 +6110,8 @@ void arm_v7m_cpu_do_interrupt(CPUState *cs) return; /* Never happens. Keep compiler happy. */ } - /* Align stack pointer. */ - /* ??? Should only do this if Configuration Control Register - STACKALIGN bit is set. */ - if (env->regs[13] & 4) { + /* Align stack pointer if the guest wants that */ + if ((env->regs[13] & 4) && (env->v7m.ccr & R_V7M_CCR_STKALIGN_MASK)) { env->regs[13] -= 4; xpsr |= 0x200; } -- 2.7.4