[llvm] [AMDGPU] Avoid repeated hash lookups (NFC) (PR #112115)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-backend-amdgpu

Author: Kazu Hirata (kazutakahirata)

<details>
<summary>Changes</summary>



---
Full diff: https://github.com/llvm/llvm-project/pull/112115.diff


1 Files Affected:

- (modified) llvm/lib/Target/AMDGPU/SIFormMemoryClauses.cpp (+2-4) 


``````````diff
diff --git a/llvm/lib/Target/AMDGPU/SIFormMemoryClauses.cpp b/llvm/lib/Target/AMDGPU/SIFormMemoryClauses.cpp
index 0d3a221970bf85..ddfa7790cabc6b 100644
--- a/llvm/lib/Target/AMDGPU/SIFormMemoryClauses.cpp
+++ b/llvm/lib/Target/AMDGPU/SIFormMemoryClauses.cpp
@@ -227,11 +227,9 @@ void SIFormMemoryClauses::collectRegUses(const MachineInstr &MI,
                            : LaneBitmask::getAll();
     RegUse &Map = MO.isDef() ? Defs : Uses;
 
-    auto Loc = Map.find(Reg);
     unsigned State = getMopState(MO);
-    if (Loc == Map.end()) {
-      Map[Reg] = std::pair(State, Mask);
-    } else {
+    auto [Loc, Inserted] = Map.try_emplace(Reg, State, Mask);
+    if (!Inserted) {
       Loc->second.first |= State;
       Loc->second.second |= Mask;
     }

``````````

</details>


https://github.com/llvm/llvm-project/pull/112115