Additional SCEV check

Ubuntu · wsmoses · commit dce5f8badca7 · 2021-08-11T20:37:12.000-04:00
diff --git a/enzyme/Enzyme/EnzymeLogic.cpp b/enzyme/Enzyme/EnzymeLogic.cpp
@@ -323,7 +323,8 @@ struct CacheAnalysis {
 
                 if (check) {
                   auto lsub = SE.getMinusSCEV(slim, SE.getAddExpr(lim, TS));
-                  if (SE.isKnownNonNegative(lsub)) {
+                  if (lsub != SE.getCouldNotCompute() &&
+                      SE.isKnownNonNegative(lsub)) {
                     return false;
                   }
                 }
@@ -384,7 +385,8 @@ struct CacheAnalysis {
 
                 if (check) {
                   auto lsub = SE.getMinusSCEV(lim, SE.getAddExpr(slim, TS));
-                  if (SE.isKnownNonNegative(lsub)) {
+                  if (lsub != SE.getCouldNotCompute() &&
+                      SE.isKnownNonNegative(lsub)) {
                     return false;
                   }
                 }

Original file line number	Diff line number	Diff line change
`@@ -323,7 +323,8 @@ struct CacheAnalysis {`
`323`	`323`
`324`	`324`	`if (check) {`
`325`	`325`	`auto lsub = SE.getMinusSCEV(slim, SE.getAddExpr(lim, TS));`
`326`		`- if (SE.isKnownNonNegative(lsub)) {`
	`326`	`+ if (lsub != SE.getCouldNotCompute() &&`
	`327`	`+ SE.isKnownNonNegative(lsub)) {`
`327`	`328`	`return false;`
`328`	`329`	`}`
`329`	`330`	`}`
`@@ -384,7 +385,8 @@ struct CacheAnalysis {`
`384`	`385`
`385`	`386`	`if (check) {`
`386`	`387`	`auto lsub = SE.getMinusSCEV(lim, SE.getAddExpr(slim, TS));`
`387`		`- if (SE.isKnownNonNegative(lsub)) {`
	`388`	`+ if (lsub != SE.getCouldNotCompute() &&`
	`389`	`+ SE.isKnownNonNegative(lsub)) {`
`388`	`390`	`return false;`
`389`	`391`	`}`
`390`	`392`	`}`