bcm5719-llvm - Project Ortega BCM5719 LLVM

	Commit message (Collapse)	Author	Age	Files	Lines
*	[SCEV] Avoid redundant computations when doing AddRec merge	Max Kazantsev	2018-11-01	1	-1/+1
\| \| \| \| \| \| \| \| \| \| \| \| \|	When we calculate a product of 2 AddRecs, we end up making quite massive computations to deduce the operands of resulting AddRec. This process can be optimized by computing all args of intermediate sum and then calling `getAddExpr` once rather than calling `getAddExpr` with intermediate result every time a new argument is computed. Differential Revision: https://reviews.llvm.org/D53189 Reviewed By: rtereshin llvm-svn: 345813
*	[SCEV] Limit AddRec "simplifications" to avoid combinatorial explosions	Max Kazantsev	2018-10-16	1	-0/+47
	SCEV's transform that turns `{A1,+,A2,+,...,+,An}<L> * {B1,+,B2,+,...,+,Bn}<L>` into a single AddRec of size `2n+1` with complex combinatorial coefficients can easily trigger exponential growth of the SCEV (in case if nothing gets folded and simplified). We tried to restrain this transform using the option `scalar-evolution-max-add-rec-size`, but its default value seems to be insufficiently small: the test attached to this patch with default value of this option `16` has a SCEV of >3M symbols (when printed out). This patch reduces the simplification limit. It is not a cure to combinatorial explosions, but at least it reduces this corner case to something more or less reasonable. Differential Revision: https://reviews.llvm.org/D53282 Reviewed By: sanjoy llvm-svn: 344584