Fix typos in code comments in src/

src/codegen/c.zig

@@ -1014,7 +1014,7 @@ pub const DeclGen = struct {
                     try writer.writeAll(", ");
                     empty = false;
                 } else {
-                    // isSignalNan is equivalent to isNan currently, and MSVC doens't have nans, so prefer nan
+                    // isSignalNan is equivalent to isNan currently, and MSVC doesn't have nans, so prefer nan
                     const operation = if (std.math.isNan(f128_val))
                         "nan"
                     else if (std.math.isSignalNan(f128_val))

src/codegen/llvm.zig

@@ -855,7 +855,7 @@ pub const Object = struct {
     /// table for every zig source field of the struct that has a corresponding
     /// LLVM struct field. comptime fields are not included. Zero-bit fields are
     /// mapped to a field at the correct byte, which may be a padding field, or
-    /// are not mapped, in which case they are sematically at the end of the
+    /// are not mapped, in which case they are semantically at the end of the
     /// struct.
     /// The value is the LLVM struct field index.
     /// This is denormalized data.

src/codegen/spirv.zig

@@ -3845,7 +3845,7 @@ const DeclGen = struct {
                     const result = try self.normalize(low_bits, info);
 
                     // Now, we need to check the overflow bits AND the sign
-                    // bit for the expceted overflow bits.
+                    // bit for the expected overflow bits.
                     // To do that, shift out everything bit the sign bit and
                     // then check what remains.
                     const shift = Temporary.init(full_result.ty, try self.constInt(full_result.ty, info.bits - 1, .direct));