[Support] Rename RoundUpToAlignment -> align.

[ruiu]

Summary

Rounding up an integer m to a nearest multiple of n where n is a power
of 2 is used very often if you are writing code to emit binary files.
RoundUpToAlignment is a small function to do that. But we found that the
function has a small but annoying issue; the name is a bit too long.
Because it is used quite often, that hurts readability.

This patch is to rename the function. The original name is kept as a
forwarder, so that submitting this patch won't immediately break Clang
and other LLVM projects. Once I update all occurrences of RoundUpToAlignment,
I'll remove the old name entirely.

[davidxl]

I could not think of a better and similarly short name -- LGTM.

[mehdi_amini]

I'd suggest alignTo

[ruiu]

• Renamed alignTo

[davidxl]

lgtm.

[mehdi_amini]

r257799

include/llvm/Support/MathExtras.h

 ///
 /// If non-zero \p Skew is specified, the return value will be a minimal
 /// integer that is greater than or equal to \p Value and equal to
 /// \p Align * N + \p Skew for some integer N. If \p Skew is larger than
 /// \p Align, its value is adjusted to '\p Skew mod \p Align'.
 ///
 /// Examples:
 /// \code
-///   RoundUpToAlignment(5, 8) = 8
-///   RoundUpToAlignment(17, 8) = 24
-///   RoundUpToAlignment(~0LL, 8) = 0
-///   RoundUpToAlignment(321, 255) = 510
-///
-///   RoundUpToAlignment(5, 8, 7) = 7
-///   RoundUpToAlignment(17, 8, 1) = 17
-///   RoundUpToAlignment(~0LL, 8, 3) = 3
-///   RoundUpToAlignment(321, 255, 42) = 552
+///   alignTo(5, 8) = 8
+///   alignTo(17, 8) = 24
+///   alignTo(~0LL, 8) = 0
+///   alignTo(321, 255) = 510
+///
+///   alignTo(5, 8, 7) = 7
+///   alignTo(17, 8, 1) = 17
+///   alignTo(~0LL, 8, 3) = 3
+///   alignTo(321, 255, 42) = 552
 /// \endcode
-inline uint64_t RoundUpToAlignment(uint64_t Value, uint64_t Align,
-                                   uint64_t Skew = 0) {
+inline uint64_t alignTo(uint64_t Value, uint64_t Align, uint64_t Skew = 0) {
   Skew %= Align;
   return (Value + Align - 1 - Skew) / Align * Align + Skew;
 }
 
+inline uint64_t RoundUpToAlignment(uint64_t Value, uint64_t Align,
+                                   uint64_t Skew = 0) {
+  return alignTo(Value, Align, Skew);
+}
+
 /// Returns the offset to the next integer (mod 2**64) that is greater than
 /// or equal to \p Value and is a multiple of \p Align. \p Align must be
 /// non-zero.
 inline uint64_t OffsetToAlignment(uint64_t Value, uint64_t Align) {
   return RoundUpToAlignment(Value, Align) - Value;
 }
 
 /// SignExtend32 - Sign extend B-bit number x to 32-bit int.