[ValueTracking] remove a FIXME for something we don't want to do; NFC

The comment was added with:
https://reviews.llvm.org/rL293773
...but there would be a cost to implement this and possibly no payoff.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@293823 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Analysis/ValueTracking.cpp b/lib/Analysis/ValueTracking.cpp
index 6c44b0d..26032e7 100644 (file)
--- a/lib/Analysis/ValueTracking.cpp
+++ b/lib/Analysis/ValueTracking.cpp
@@ -797,10 +797,6 @@ static void computeKnownBitsFromAssume(const Value *V, APInt &KnownZero,
   // FIXME: Publish a warning/remark that we have encountered UB or the compiler
   // is broken.
 
-  // FIXME: Implement a stronger version of "I give up" by invalidating/clearing
-  // the assumption cache. This should indicate that the cache is corrupted so
-  // future callers will not waste time repopulating it with faulty assumptions.
-
   if ((KnownZero & KnownOne) != 0) {
     KnownZero.clearAllBits();
     KnownOne.clearAllBits();

diff --git a/test/Transforms/InstSimplify/assume.ll b/test/Transforms/InstSimplify/assume.ll
index 2edcc0c..4255238 100644 (file)
--- a/test/Transforms/InstSimplify/assume.ll
+++ b/test/Transforms/InstSimplify/assume.ll
@@ -28,8 +28,7 @@ define i64 @PR31809() {
 
 ; Similar to above: there's no way to know which assumption is truthful,
 ; so just don't crash. The second icmp+assume gets processed later, so that
-; determines the return value. This can be improved by permanently invalidating
-; the cached assumptions for this function. 
+; determines the return value.
 
 define i8 @conflicting_assumptions(i8 %x) {
 ; CHECK-LABEL: @conflicting_assumptions(