commit cfeca5f93617a93b597bdb82d3692a64e2850243
author MLIR Team <no-reply@google.com> Tue Aug 14 12:43:51 2018 -0700
committer jpienaar <jpienaar@google.com> Fri Mar 29 12:59:47 2019 -0700
tree e01b507190714bcaab46fa2f4697a89c3fd5a862
parent 3cdb8aaa77d069bf33aa9ab1511309643570992d

Add AffineMap::isIdentity helper function.

PiperOrigin-RevId: 208694482

lib/IR/AffineMap.cpp

diff --git a/lib/IR/AffineMap.cpp b/lib/IR/AffineMap.cpp
index 4bd224d..8dc0d1f 100644
--- a/lib/IR/AffineMap.cpp
+++ b/lib/IR/AffineMap.cpp
@@ -27,6 +27,19 @@
     : numDims(numDims), numSymbols(numSymbols), numResults(numResults),
       results(results), rangeSizes(rangeSizes) {}
 
+bool AffineMap::isIdentity() const {
+  if (getNumDims() != getNumResults())
+    return false;
+  ArrayRef<AffineExpr *> results = getResults();
+  for (unsigned i = 0; i < getNumDims(); ++i) {
+    auto *expr = results[i];
+    if (!isa<AffineDimExpr>(expr) ||
+        cast<AffineDimExpr>(expr)->getPosition() != i)
+      return false;
+  }
+  return true;
+}
+
 /// Simplify add expression. Return nullptr if it can't be simplified.
 AffineExpr *AffineBinaryOpExpr::simplifyAdd(AffineExpr *lhs, AffineExpr *rhs,
                                             MLIRContext *context) {