Merge pull request #1116 from rdmarsh2/rdmarsh/cpp/ir-guards-perf

jbj · web-flow · commit 690e2ae514db · 2019-03-15T11:35:15.000+01:00
C++: fix cartesian product in IRGuards.qll
diff --git a/cpp/ql/src/semmle/code/cpp/controlflow/IRGuards.qll b/cpp/ql/src/semmle/code/cpp/controlflow/IRGuards.qll
@@ -381,9 +381,7 @@ cached class IRGuardCondition extends Instruction {
 }
 
 private ConditionalBranchInstruction get_branch_for_condition(Instruction guard) {
-  exists(ConditionalBranchInstruction branch|
-    branch.getCondition() = guard
-  )
+  result.getCondition() = guard
   or
   exists(LogicalNotInstruction cond | result = get_branch_for_condition(cond) and cond.getUnary() = guard)
 }

Original file line number	Diff line number	Diff line change
`@@ -381,9 +381,7 @@ cached class IRGuardCondition extends Instruction {`
`381`	`381`	`}`
`382`	`382`
`383`	`383`	`private ConditionalBranchInstruction get_branch_for_condition(Instruction guard) {`
`384`		`- exists(ConditionalBranchInstruction branch\|`
`385`		`- branch.getCondition() = guard`
`386`		`- )`
	`384`	`+ result.getCondition() = guard`
`387`	`385`	`or`
`388`	`386`	`exists(LogicalNotInstruction cond \| result = get_branch_for_condition(cond) and cond.getUnary() = guard)`
`389`	`387`	`}`