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From: Richard Henderson <richard.henderson@linaro.org>
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Date: Thu, 5 Oct 2017 12:34:53 -0400
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Subject: Re: [Qemu-devel] [PATCH 08/20] target/arm: Don't warn about
 exception return with PC low bit set for v8M
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To: Peter Maydell <peter.maydell@linaro.org>, qemu-arm@nongnu.org, qemu-devel@nongnu.org
Cc: patches@linaro.org

On 10/05/2017 12:32 PM, Richard Henderson wrote:
>     if (env->regs[15] & 1) {
>         if (!arm_feature(env, ARM_FEATURE_V8)) {
>             qemu_log_mask(...);
>         }
>         env->regs[15] &= ~1U;
>     }

Bah.  Even better to move the bit clear statement before the feature check.
The two loads from env->regs[15] will no longer be separated by a function call
and therefore CSEd by the compiler.


r~