checks.adb (Minimize_Eliminate_Overflow_Checks): Dont reanalyze if/case expression...

checks.adb (Minimize_Eliminate_Overflow_Checks): Dont reanalyze if/case expression if nothing has changed (just reexpand).

2012-10-04  Robert Dewar  <dewar@adacore.com>

	* checks.adb (Minimize_Eliminate_Overflow_Checks): Dont reanalyze
	if/case expression if nothing has changed (just reexpand). Stops
	case expression from generating incorrect temporary.
	* exp_ch4.adb (Expand_Compare_Minimize_Eliminate_Overflow):
	Fix cut and paste typo for range analysis in NE (not equal) case.
	* sem_eval.adb (Compile_Time_Compare): Small optimization to
	catch some more cases.
	* types.ads (Suppressed_Or_Checked): New subtype of
	Overflow_Check_Type.

From-SVN: r192070