commit aac7c650a6cac09d42c5fda8d3761bc9c871ff03
author Benjamin Kramer <benny.kra@googlemail.com> Tue Aug 28 13:08:13 2012 +0000
committer Benjamin Kramer <benny.kra@googlemail.com> Tue Aug 28 13:08:13 2012 +0000
tree 9397d631f2aeda94317ab5f84c34aa2870ff612a
parent a694e2a6910a33596ca706e2c6fc713f02b64c50

InstCombine: Guard the transform introduced in r162743 against large ints and non-const shifts.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@162751 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Transforms/InstCombine/InstCombineMulDivRem.cpp

diff --git a/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp b/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
index 5eba463..65a64b8 100644
--- a/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
+++ b/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
@@ -464,11 +464,11 @@
 
   // Udiv ((Lshl x, C1) , C2) ->  x / (C2 * 1<<C1);
   if (ConstantInt *C2 = dyn_cast<ConstantInt>(Op1)) {
-    Value *X = 0, *C1 = 0;
-    if (match(Op0, m_LShr(m_Value(X), m_Value(C1))) && C2->getBitWidth() < 65) {
-      uint64_t NC = cast<ConstantInt>(C2)->getZExtValue() *
-                    (1<< cast<ConstantInt>(C1)->getZExtValue());
-      return BinaryOperator::CreateUDiv(X, ConstantInt::get(I.getType(), NC));
+    Value *X;
+    ConstantInt *C1;
+    if (match(Op0, m_LShr(m_Value(X), m_ConstantInt(C1)))) {
+      APInt NC = C2->getValue().shl(C1->getZExtValue());
+      return BinaryOperator::CreateUDiv(X, Builder->getInt(NC));
     }
   }
 
@@ -545,11 +545,11 @@
 
   // Sdiv ((Ashl x, C1) , C2) ->  x / (C2 * 1<<C1);
   if (ConstantInt *C2 = dyn_cast<ConstantInt>(Op1)) {
-    Value *X = 0, *C1 = 0;
-    if (match(Op0, m_AShr(m_Value(X), m_Value(C1))) && C2->getBitWidth() < 65) {
-      uint64_t NC = cast<ConstantInt>(C2)->getZExtValue() *
-                    (1<< cast<ConstantInt>(C1)->getZExtValue());
-      return BinaryOperator::CreateSDiv(X, ConstantInt::get(I.getType(), NC));
+    Value *X;
+    ConstantInt *C1;
+    if (match(Op0, m_AShr(m_Value(X), m_ConstantInt(C1)))) {
+      APInt NC = C2->getValue().shl(C1->getZExtValue());
+      return BinaryOperator::CreateSDiv(X, Builder->getInt(NC));
     }
   }