From d81fa76f3a6b698d9d76e610eb0a8c0f7ea82eaf Mon Sep 17 00:00:00 2001
From: Arjun P <arjunpitchanathan@gmail.com>
Date: Thu, 31 Mar 2022 12:34:33 +0100
Subject: [PATCH] [MLIR][Presburger]
 MultiAffineFunction:eliminateRedundantLocalId: fix bug where local offset was
 not considered

Previously, when updating the outputs matrix, the local offset was not being considered.

Reviewed By: Groverkss

Differential Revision: https://reviews.llvm.org/D122812
---
 mlir/lib/Analysis/Presburger/PWMAFunction.cpp      |  3 ++-
 .../Analysis/Presburger/PWMAFunctionTest.cpp       | 22 +++++++++++++++++++---
 2 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/mlir/lib/Analysis/Presburger/PWMAFunction.cpp b/mlir/lib/Analysis/Presburger/PWMAFunction.cpp
index 42b2511..d00bc2d7 100644
--- a/mlir/lib/Analysis/Presburger/PWMAFunction.cpp
+++ b/mlir/lib/Analysis/Presburger/PWMAFunction.cpp
@@ -110,7 +110,8 @@ void MultiAffineFunction::removeIdRange(IdKind kind, unsigned idStart,
 
 void MultiAffineFunction::eliminateRedundantLocalId(unsigned posA,
                                                     unsigned posB) {
-  output.addToColumn(posB, posA, /*scale=*/1);
+  unsigned localOffset = getIdKindOffset(IdKind::Local);
+  output.addToColumn(localOffset + posB, localOffset + posA, /*scale=*/1);
   IntegerPolyhedron::eliminateRedundantLocalId(posA, posB);
 }
 
diff --git a/mlir/unittests/Analysis/Presburger/PWMAFunctionTest.cpp b/mlir/unittests/Analysis/Presburger/PWMAFunctionTest.cpp
index 79139de..27d0252 100644
--- a/mlir/unittests/Analysis/Presburger/PWMAFunctionTest.cpp
+++ b/mlir/unittests/Analysis/Presburger/PWMAFunctionTest.cpp
@@ -157,19 +157,35 @@ TEST(PWMAFunction, valueAt) {
 }
 
 TEST(PWMAFunction, removeIdRangeRegressionTest) {
-  PWMAFunction pwafA = parsePWMAF(
+  PWMAFunction pwmafA = parsePWMAF(
       /*numInputs=*/2, /*numOutputs=*/1,
       {
           {"(x, y) : (x == 0, y == 0, x - 2*(x floordiv 2) == 0, y - 2*(y "
            "floordiv 2) == 0)",
            {{0, 0, 0, 0, 0}}} // (0, 0)
       });
-  PWMAFunction pwafB = parsePWMAF(
+  PWMAFunction pwmafB = parsePWMAF(
       /*numInputs=*/2, /*numOutputs=*/1,
       {
           {"(x, y) : (x - 11*y == 0, 11*x - y == 0, x - 2*(x floordiv 2) == 0, "
            "y - 2*(y floordiv 2) == 0)",
            {{0, 0, 0, 0, 0}}} // (0, 0)
       });
-  EXPECT_TRUE(pwafA.isEqual(pwafB));
+  EXPECT_TRUE(pwmafA.isEqual(pwmafB));
+}
+
+TEST(PWMAFunction, eliminateRedundantLocalIdRegressionTest) {
+  PWMAFunction pwmafA = parsePWMAF(
+      /*numInputs=*/2, /*numOutputs=*/1,
+      {
+          {"(x, y) : (x - 2*(x floordiv 2) == 0, x - 2*y == 0)",
+           {{0, 1, 0, 0}}} // (0, 0)
+      });
+  PWMAFunction pwmafB = parsePWMAF(
+      /*numInputs=*/2, /*numOutputs=*/1,
+      {
+          {"(x, y) : (x - 2*(x floordiv 2) == 0, x - 2*y == 0)",
+           {{1, -1, 0, 0}}} // (0, 0)
+      });
+  EXPECT_TRUE(pwmafA.isEqual(pwmafB));
 }
-- 
2.7.4