[libc][math] Fix division by infinity in fputil::div (#152092)

Signed-off-by: Krishna Pandey <[email protected]>

Author: krishna2803

libc/src/__support/FPUtil/generic/div.h

@@ -78,7 +78,7 @@ div(InType x, InType y) {
     }
 
     if (y_bits.is_inf())
-      return OutFPBits::inf(result_sign).get_val();
+      return OutFPBits::zero(result_sign).get_val();
 
     if (y_bits.is_zero()) {
       if (x_bits.is_zero()) {

libc/test/src/math/smoke/DivTest.h

@@ -47,6 +47,11 @@ class DivTest : public LIBC_NAMESPACE::testing::FEnvSafeTest {
     EXPECT_FP_EQ(neg_inf, func(in.neg_inf, in.zero));
     EXPECT_FP_EQ(neg_inf, func(in.inf, in.neg_zero));
     EXPECT_FP_EQ(inf, func(in.neg_inf, in.neg_zero));
+    EXPECT_FP_EQ(zero, func(in.min_normal, in.inf));
+    EXPECT_FP_EQ(zero, func(in.zero, in.inf));
+    EXPECT_FP_EQ(zero, func(in.neg_zero, in.neg_inf));
+    EXPECT_FP_EQ(neg_zero, func(in.min_normal, in.neg_inf));
+    EXPECT_FP_EQ(neg_zero, func(in.zero, in.neg_inf));
   }
 
   void test_division_by_zero(DivFunc func) {