[llvm] [InstCombine] Use more inline elements in a SmallVector (PR #100942)

[via llvm-commits]

llvmbot wrote:


<!--LLVM PR SUMMARY COMMENT-->

@llvm/pr-subscribers-llvm-transforms

Author: Kazu Hirata (kazutakahirata)

<details>
<summary>Changes</summary>

The 4 inline elements only cover 58% of cases encountered here during
the compilation of X86ISelLowering.cpp.ll, a .ll version of
X86ISelLowering.cpp.

The 8 inline elements cover 96% and save 0.27% of heap allocations.


---
Full diff: https://github.com/llvm/llvm-project/pull/100942.diff


1 Files Affected:

- (modified) llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp (+1-1) 


``````````diff
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
index f6c4b6e180937..e61480d7542d7 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp
@@ -1500,7 +1500,7 @@ Instruction *InstCombinerImpl::visitCallInst(CallInst &CI) {
   // Don't try to simplify calls without uses. It will not do anything useful,
   // but will result in the following folds being skipped.
   if (!CI.use_empty()) {
-    SmallVector<Value *, 4> Args;
+    SmallVector<Value *, 8> Args;
     Args.reserve(CI.arg_size());
     for (Value *Op : CI.args())
       Args.push_back(Op);

``````````

</details>


https://github.com/llvm/llvm-project/pull/100942