[llvm] add power function to APInt (PR #122788)

[Craig Topper via llvm-commits]

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@@ -29,6 +29,59 @@ TEST(APIntTest, ValueInit) {
   EXPECT_TRUE(!Zero.sext(64));
 }
 
+// Test that 0^5 == 0
+TEST(APIntTest, PowZeroTo5) {
+  APInt Zero = APInt();
+  EXPECT_TRUE(!Zero);
+  APInt ZeroTo5 = APIntOps::pow(Zero, 5);
+  EXPECT_TRUE(!ZeroTo5);
+}
+
+// Test that 1^16 == 1
+TEST(APIntTest, PowOneTo16) {
+  APInt One = APInt::getZero(32) + 1;
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topperc wrote:

`APInt One(32, 1)`

https://github.com/llvm/llvm-project/pull/122788