Commit 60fba59a authored by Peter Maydell's avatar Peter Maydell
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target/arm: Clean excReturn bits when tail chaining 



The TailChain() pseudocode specifies that a tail chaining
exception should sanitize the excReturn all-ones bits and
(if there is no FPU) the excReturn FType bits; we weren't
doing this.

Signed-off-by: default avatarPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: default avatarRichard Henderson <richard.henderson@linaro.org>
Message-id: 20190416125744.27770-14-peter.maydell@linaro.org
parent 3cd6726f

target/arm/helper.c

+8 −0
Original line number Diff line number Diff line
@@ -8076,6 +8076,14 @@ static void v7m_exception_taken(ARMCPU *cpu, uint32_t lr, bool dotailchain, 
    qemu_log_mask(CPU_LOG_INT, "...taking pending %s exception %d\n",

                  targets_secure ? "secure" : "nonsecure", exc);



    if (dotailchain) {

        /* Sanitize LR FType and PREFIX bits */

        if (!arm_feature(env, ARM_FEATURE_VFP)) {

            lr |= R_V7M_EXCRET_FTYPE_MASK;

        }

        lr = deposit32(lr, 24, 8, 0xff);

    }



    if (arm_feature(env, ARM_FEATURE_V8)) {

        if (arm_feature(env, ARM_FEATURE_M_SECURITY) &&

            (lr & R_V7M_EXCRET_S_MASK)) {