[NFC][ConstantRange] Add 'icmp' helper method

"Does the predicate hold between two ranges?"

Not very surprisingly, some places were already doing this check,
without explicitly naming the algorithm, cleanup them all.

1 files changed, 48 insertions, 1 deletions

diff --git a/llvm/unittests/IR/ConstantRangeTest.cpp b/llvm/unittests/IR/ConstantRangeTest.cpp
index 12362b9..f8816e4 100644
--- a/llvm/unittests/IR/ConstantRangeTest.cpp
+++ b/llvm/unittests/IR/ConstantRangeTest.cpp
@@ -6,9 +6,10 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "llvm/IR/ConstantRange.h"
 #include "llvm/ADT/BitVector.h"
+#include "llvm/ADT/Sequence.h"
 #include "llvm/ADT/SmallBitVector.h"
-#include "llvm/IR/ConstantRange.h"
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/Operator.h"
 #include "llvm/Support/KnownBits.h"
@@ -1509,6 +1510,52 @@ TEST(ConstantRange, MakeSatisfyingICmpRegion) {
       ConstantRange(APInt(8, 4), APInt(8, -128)));
 }
 
+static bool icmp(CmpInst::Predicate Pred, const APInt &LHS, const APInt &RHS) {
+  switch (Pred) {
+  case CmpInst::Predicate::ICMP_EQ:
+    return LHS.eq(RHS);
+  case CmpInst::Predicate::ICMP_NE:
+    return LHS.ne(RHS);
+  case CmpInst::Predicate::ICMP_UGT:
+    return LHS.ugt(RHS);
+  case CmpInst::Predicate::ICMP_UGE:
+    return LHS.uge(RHS);
+  case CmpInst::Predicate::ICMP_ULT:
+    return LHS.ult(RHS);
+  case CmpInst::Predicate::ICMP_ULE:
+    return LHS.ule(RHS);
+  case CmpInst::Predicate::ICMP_SGT:
+    return LHS.sgt(RHS);
+  case CmpInst::Predicate::ICMP_SGE:
+    return LHS.sge(RHS);
+  case CmpInst::Predicate::ICMP_SLT:
+    return LHS.slt(RHS);
+  case CmpInst::Predicate::ICMP_SLE:
+    return LHS.sle(RHS);
+  default:
+    llvm_unreachable("Not an ICmp predicate!");
+  }
+}
+
+void ICmpTestImpl(CmpInst::Predicate Pred) {
+  unsigned Bits = 4;
+  EnumerateTwoConstantRanges(
+      Bits, [&](const ConstantRange &CR1, const ConstantRange &CR2) {
+        bool Exhaustive = true;
+        ForeachNumInConstantRange(CR1, [&](const APInt &N1) {
+          ForeachNumInConstantRange(
+              CR2, [&](const APInt &N2) { Exhaustive &= icmp(Pred, N1, N2); });
+        });
+        EXPECT_EQ(CR1.icmp(Pred, CR2), Exhaustive);
+      });
+}
+
+TEST(ConstantRange, ICmp) {
+  for (auto Pred : seq<unsigned>(CmpInst::Predicate::FIRST_ICMP_PREDICATE,
+                                 1 + CmpInst::Predicate::LAST_ICMP_PREDICATE))
+    ICmpTestImpl((CmpInst::Predicate)Pred);
+}
+
 TEST(ConstantRange, MakeGuaranteedNoWrapRegion) {
   const int IntMin4Bits = 8;
   const int IntMax4Bits = 7;