[clang] [llvm] [LLVM][APFloat] Add APFloat support for 8-bit UE5M3 type (PR #210720)

[Durgadoss R via cfe-commits]

================
@@ -9860,6 +9898,298 @@ TEST(APFloatTest, ConvertDoubleToE8M0FNU) {
   EXPECT_EQ(status, APFloat::opUnderflow | APFloat::opInexact);
 }
 
+TEST(APFloatTest, Float8E5M3FNUValues) {
+  // High end of the range
+  auto test = APFloat(APFloat::Float8E5M3FNU(), "0x1.c0p16");
+  EXPECT_EQ(0x1.c0p16, test.convertToDouble());
+
+  test = APFloat(APFloat::Float8E5M3FNU(), "0x1.c0p15");
+  EXPECT_EQ(0x1.cp15, test.convertToDouble());
+
+  test = APFloat(APFloat::Float8E5M3FNU(), "0x1.0p14");
+  EXPECT_EQ(0x1.0p14, test.convertToDouble());
+
+  // tests the fix in makeLargest()
+  test = APFloat::getLargest(APFloat::Float8E5M3FNU());
+  EXPECT_EQ(0x1.cp16, test.convertToDouble());
+
+  // tests overflow to nan
+  APFloat nan = APFloat(APFloat::Float8E5M3FNU(), "nan");
+  test = APFloat(APFloat::Float8E5M3FNU(), "0x1.e0p+16");
+  EXPECT_TRUE(test.bitwiseIsEqual(nan));
+
+  // Mid of the range
+  test = APFloat(APFloat::Float8E5M3FNU(), "0x1.0p0");
+  EXPECT_EQ(1.0, test.convertToDouble());
+
+  test = APFloat(APFloat::Float8E5M3FNU(), "0x1.0p1");
+  EXPECT_EQ(2.0, test.convertToDouble());
+
+  test = APFloat(APFloat::Float8E5M3FNU(), "0x1.0p2");
+  EXPECT_EQ(4.0, test.convertToDouble());
+
+  // Low end of the range
+  test = APFloat(APFloat::Float8E5M3FNU(), "0x1.0p-12");
+  EXPECT_EQ(0x1.0p-12, test.convertToDouble());
+
+  test = APFloat(APFloat::Float8E5M3FNU(), "0x1.0p-13");
+  EXPECT_EQ(0x1.0p-13, test.convertToDouble());
+
+  test = APFloat(APFloat::Float8E5M3FNU(), "0x1.0p-14");
+  EXPECT_EQ(0x1.0p-14, test.convertToDouble());
+  EXPECT_TRUE(test.isSmallestNormalized());
+
+  // Smallest value
+  test = APFloat::getSmallest(APFloat::Float8E5M3FNU());
+  EXPECT_EQ(0x1.0p-17, test.convertToDouble());
----------------
durga4github wrote:

same, duplicate test (line 2414) and can be removed

https://github.com/llvm/llvm-project/pull/210720