remove expensive copy of options passed

[mahesh-attarde]

Codegen option is passed copy by value which 138 bytes of copy and used as read-only. Making pass by const reference.

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[llvmbot]

@llvm/pr-subscribers-backend-x86

Author: None (mahesh-attarde)

Changes

Codegen option is passed copy by value which 138 bytes of copy and used as read-only. Making pass by const reference.

---

Full diff: https://github.com/llvm/llvm-project/pull/82577.diff

2 Files Affected:

• (modified) llvm/include/llvm/Passes/CodeGenPassBuilder.h (+2-1)
• (modified) llvm/lib/Target/X86/X86CodeGenPassBuilder.cpp (+1-1)

diff --git a/llvm/include/llvm/Passes/CodeGenPassBuilder.h b/llvm/include/llvm/Passes/CodeGenPassBuilder.h
index 80bbfb75185a9c..fce59611beb6e9 100644
--- a/llvm/include/llvm/Passes/CodeGenPassBuilder.h
+++ b/llvm/include/llvm/Passes/CodeGenPassBuilder.h
@@ -114,7 +114,8 @@ namespace llvm {
 /// construction.
 template <typename DerivedT> class CodeGenPassBuilder {
 public:
-  explicit CodeGenPassBuilder(LLVMTargetMachine &TM, CGPassBuilderOption Opts,
+  explicit CodeGenPassBuilder(LLVMTargetMachine &TM,
+                              const CGPassBuilderOption &Opts,
                               PassInstrumentationCallbacks *PIC)
       : TM(TM), Opt(Opts), PIC(PIC) {
     // Target could set CGPassBuilderOption::MISchedPostRA to true to achieve
diff --git a/llvm/lib/Target/X86/X86CodeGenPassBuilder.cpp b/llvm/lib/Target/X86/X86CodeGenPassBuilder.cpp
index 4a11dd2e31acde..4a7c9543645e7d 100644
--- a/llvm/lib/Target/X86/X86CodeGenPassBuilder.cpp
+++ b/llvm/lib/Target/X86/X86CodeGenPassBuilder.cpp
@@ -22,7 +22,7 @@ namespace {
 class X86CodeGenPassBuilder : public CodeGenPassBuilder<X86CodeGenPassBuilder> {
 public:
   explicit X86CodeGenPassBuilder(LLVMTargetMachine &TM,
-                                 CGPassBuilderOption Opts,
+                                 const CGPassBuilderOption &Opts,
                                  PassInstrumentationCallbacks *PIC)
       : CodeGenPassBuilder(TM, Opts, PIC) {}
   void addPreISel(AddIRPass &addPass) const;

[phoebewang]

LGTM.

[KanRobert]

LGTM

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