From: Nick Lewycky <nicholas@mxc.ca>
Date: Sat, 14 Jul 2007 04:28:04 +0000 (+0000)
Subject: Use maximal intersection algorithm exclusively. Fixes miscompile bug.
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=a73d11efd435cfa5ab275400c9881724f9224ca0;p=oota-llvm.git

Use maximal intersection algorithm exclusively. Fixes miscompile bug.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39852 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Transforms/Scalar/PredicateSimplifier.cpp b/lib/Transforms/Scalar/PredicateSimplifier.cpp
index 7b0a413f506..cea218a8e33 100644
--- a/lib/Transforms/Scalar/PredicateSimplifier.cpp
+++ b/lib/Transforms/Scalar/PredicateSimplifier.cpp
@@ -938,7 +938,7 @@ namespace {
             std::lower_bound(begin(), E, std::make_pair(Subtree, empty), swo);
 
         if (I != end() && I->first == Subtree) {
-          ConstantRange CR2 = I->second.intersectWith(CR);
+          ConstantRange CR2 = I->second.maximalIntersectWith(CR);
           assert(!CR2.isEmptySet() && !CR2.isSingleElement() &&
                  "Invalid union of ranges.");
           I->second = CR2;
@@ -970,18 +970,18 @@ namespace {
       ConstantRange Range(CR.getBitWidth());
 
       if (LV_s == SGT_BIT) {
-        Range = Range.intersectWith(makeConstantRange(
+        Range = Range.maximalIntersectWith(makeConstantRange(
                     hasEQ ? ICmpInst::ICMP_SGE : ICmpInst::ICMP_SGT, CR));
       } else if (LV_s == SLT_BIT) {
-        Range = Range.intersectWith(makeConstantRange(
+        Range = Range.maximalIntersectWith(makeConstantRange(
                     hasEQ ? ICmpInst::ICMP_SLE : ICmpInst::ICMP_SLT, CR));
       }
 
       if (LV_u == UGT_BIT) {
-        Range = Range.intersectWith(makeConstantRange(
+        Range = Range.maximalIntersectWith(makeConstantRange(
                     hasEQ ? ICmpInst::ICMP_UGE : ICmpInst::ICMP_UGT, CR));
       } else if (LV_u == ULT_BIT) {
-        Range = Range.intersectWith(makeConstantRange(
+        Range = Range.maximalIntersectWith(makeConstantRange(
                     hasEQ ? ICmpInst::ICMP_ULE : ICmpInst::ICMP_ULT, CR));
       }
 
@@ -1104,7 +1104,7 @@ namespace {
       switch (LV) {
       default: assert(!"Impossible lattice value!");
       case NE:
-        return CR1.intersectWith(CR2).isEmptySet();
+        return CR1.maximalIntersectWith(CR2).isEmptySet();
       case ULT:
         return CR1.getUnsignedMax().ult(CR2.getUnsignedMin());
       case ULE:
@@ -1170,7 +1170,7 @@ namespace {
         unsigned i = VN.valueNumber(*I, Subtree);
         ConstantRange CR_Kill = i ? range(i, Subtree) : range(*I);
         if (CR_Kill.isFullSet()) continue;
-        Merged = Merged.intersectWith(CR_Kill);
+        Merged = Merged.maximalIntersectWith(CR_Kill);
       }
 
       if (Merged.isFullSet() || Merged == CR_New) return;
@@ -1180,7 +1180,7 @@ namespace {
 
     void applyRange(unsigned n, const ConstantRange &CR,
                     DomTreeDFS::Node *Subtree, VRPSolver *VRP) {
-      ConstantRange Merged = CR.intersectWith(range(n, Subtree));
+      ConstantRange Merged = CR.maximalIntersectWith(range(n, Subtree));
       if (Merged.isEmptySet()) {
         markBlock(VRP);
         return;
@@ -1270,14 +1270,14 @@ namespace {
       ConstantRange CR2 = range(n2, Subtree);
 
       if (!CR1.isSingleElement()) {
-        ConstantRange NewCR1 = CR1.intersectWith(create(LV, CR2));
+        ConstantRange NewCR1 = CR1.maximalIntersectWith(create(LV, CR2));
         if (NewCR1 != CR1)
           applyRange(n1, NewCR1, Subtree, VRP);
       }
 
       if (!CR2.isSingleElement()) {
-        ConstantRange NewCR2 = CR2.intersectWith(create(reversePredicate(LV),
-                                                        CR1));
+        ConstantRange NewCR2 = CR2.maximalIntersectWith(
+                                       create(reversePredicate(LV), CR1));
         if (NewCR2 != CR2)
           applyRange(n2, NewCR2, Subtree, VRP);
       }