[llvm] [LLVM][DWARF] Make dwarf::getDebugNamesBucketCount return a pair. (PR #83047)

[Felipe de Azevedo Piovezan via llvm-commits]

================
@@ -616,20 +616,21 @@ enum AcceleratorTable {
 // Uniquify the string hashes and calculate the bucket count for the
 // DWARF v5 Accelerator Table. NOTE: This function effectively consumes the
 // 'hashes' input parameter.
-inline uint32_t getDebugNamesBucketCount(MutableArrayRef<uint32_t> hashes,
-                                         uint32_t &uniqueHashCount) {
-  uint32_t BucketCount = 0;
+inline std::pair<uint32_t, uint32_t> getDebugNamesBucketAndHashCount(
+    MutableArrayRef<uint32_t> hashes) {
+  uint32_t uniqueHashCount = 0;
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felipepiovezan wrote:

we should avoid declaring-then-initializing as much as possible, this should be moved to where the variable is actually computed:

```
uint32_t uniqueHashCount = llvm::unique(hashes) - hashes.begin();
```

https://github.com/llvm/llvm-project/pull/83047