[Mono-devel-list] [PATCH] Faster array bounds checking

[Ben Maurer]

Hello,

The attached patch makes mini use the compare reg,membase operation when
it is doing array bounds checking. so, rather than:

mov length_reg, [array+length_offset]
cmp index,length_reg

we get

cmp index, [array+length_offset]

The speedup was pretty big for a simple test case:
[benm at Ben tmp]$ /devel/mono/mono/mini/mono array.exe
14760
[benm at Ben tmp]$ mono array.exe
16557

The number is the time in ms to do an array scan (the test is attached).

I got no regressions on the test suites.

Miguel has recommended that to avoid any legal issues, I license this
under the x11 license, so:

This patch is licensed under the MIT/X11 License.

-- Ben
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