RFR(S) 8252481 Remove excessive include of memTracker.hpp

[Lois Foltan]

Looks good Ioi!
Lois

On 8/28/2020 1:21 AM, Ioi Lam wrote:
> https://bugs.openjdk.java.net/browse/JDK-8252481
> http://cr.openjdk.java.net/~iklam/jdk16/8252481-excessive-memTracker-hpp.v01/ 
>
>
> memTracker.hpp is included by 847 out of 971 .o files in the HotSpot 
> build.
>
> Most of these are caused by these header files:
>
> jfrAllocation.hpp -- completely unnecessary
>
> allocation.hpp, allocation.inline.hpp -- the use of CURRENT_PC can be 
> avoid by calling this function instead:
>
> char* AllocateHeap(size_t size,
>                    MEMFLAGS flags,
>                    AllocFailType alloc_failmode /* = 
> AllocFailStrategy::EXIT_OOM*/) {
>   return AllocateHeap(size, flags, CALLER_PC);
> }
>
>
> ======================
>
> Before:
>
> $ cd build/linux-x64
> $ find hotspot -name \*.o | wc -l
> 971
> $ find hotspot -name \*.d | xargs grep -l memTracker.hpp | wc -l
> 847
> $ find hotspot -name \*.d | xargs cat | wc -l
> 528505
>
> After:
>
> $ find hotspot -name \*.d | xargs grep -l memTracker.hpp | wc -l
> 95
> $ find hotspot -name \*.d | xargs cat | wc -l
> 512731
>
> The total number of included header files has reduced for about 3%
>
> 512731 / 528505 = 0.970
>
> ======================
>
> Testing -- I am running mach5 tiers 1-4.