RFR(XS) 8032894: Remove dead code in Pressure::lower

Vladimir Kozlov vladimir.kozlov at oracle.com
Wed Jan 29 10:53:24 PST 2014

What is initial state of _current_pressure, _high_pressure_limit, 
_final_pressure? How we can get case (_current_pressure == 
_high_pressure_limit)? May be we should replace the code with assert:

assert(_current_pressure <= _final_pressure


On 1/29/14 4:09 AM, Niclas Adlertz wrote:
> Hi all,
> When building the physical IFG, we step backwards in each block, and
> remove things that are defined from the LIVE_OUT, (and lower the current
> pressure) and add input to the LIVE_OUT (and raising the current
> pressure). Each time we lower or raise the current pressure, we check if
> it's bigger than the current maximum pressure, known as final_pressure.
> However the final_pressure can never increase when removing definitions
> (i.e. lower the current pressure) so the check for a new final_pressure
> in Pressure::lower is useless.
> webrev: http://cr.openjdk.java.net/~adlertz/JDK-8032894/webrev00/
> bug: https://bugs.openjdk.java.net/browse/JDK-8032894
> Kind Regards,
> Niclas Adlertz

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