[llvm] [NFC] Various Cleanup in StackColoring, StackSlotColoring, LiveStacks (PR #143931)

[via llvm-commits]

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@@ -795,6 +795,41 @@ using stack_float_t = volatile float;
 using stack_float_t = float;
 #endif
 
+/// Returns the number of digits in the given integer.
+inline int NumDigitsBase10(uint64_t X) {
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Ralender wrote:

Here is the split off. https://github.com/llvm/llvm-project/pull/165479

https://github.com/llvm/llvm-project/pull/143931