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Re: [RFA (revised)] sh-sim, expand the opcode table


Joern Rennecke wrote:
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Hi Joern,

Here are some benchmark results.  Following your advice, I took the
arith-rand test, increased its main loop count until it took around
10 seconds to run on my test machine, and tested it against the eight
optimization combinations that are tested for in the gcc torture test
[see methodology notes attached]


I found that my change increased the runtime by 1.5 to 2 percent (even when I added the new instructions that I'm working on).


Was that with or without ACE_FAST ?

Forgot to define ACE_FAST -- new results attached (just for the 16-bit case).


That didn't seem too bad to me, but I took some advice from Alex
Oliva and tried simply changing the sh_jmp_table from char to short.
This much simpler change increased the runtime by only 0.5 to 1
percent, at the cost of 64k more data space.


That makese sense... but what is the cost of adding the new instructions?

Imprecisely speaking, they did not seem to make any difference at all. The number of new insns is actually not that great -- they only bring the switch statement up to about 290 cases.



		orig	16bit	%inc

O0		9.048	9.049	.01
		9.050	9.035	0
O1		5.557	5.592	.63
		5.550	5.595	.81
O2		5.465	5.538	1.3
		5.460	5.535	1.4
O3		4.784	4.830	.96
		4.775	4.820	.94
O3 omit		4.695	4.747	1.1
		4.690	4.750	1.3
O3 omit unroll	4.694	4.738	.94
		4.695	4.735	.85
O3 -g		4.786	4.841	1.1
		4.780	4.840	1.3
Os		5.475	5.525	.91
		5.475	5.515	.73

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