RPCS3/llvm-mirror
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-11-24 03:33:20 +01:00
Code Issues Projects Releases Wiki Activity

IR: Use SmallVector instead of std::vector of TrackingMDRef

Browse Source 
Don't use std::vector<TrackingMDRef>, since (at least in some versions
of libc++) std::vector apparently copies values on grow operations
instead of moving them.  Found this when I was temporarily deleting the
copy constructor for TrackingMDRef to investigate a performance
bottleneck.

llvm-svn: 266909
This commit is contained in:
Duncan P. N. Exon Smith 2016-04-20 20:14:09 +00:00
parent f75e13b583
commit 9e2408123d
3 changed files with 12 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
include/llvm/IR/DIBuilder.h
View File

@ -51,7 +51,11 @@ namespace llvm {
bool AllowUnresolvedNodes;
/// Each subprogram's preserved local variables.
DenseMap<MDNode *, std::vector<TrackingMDNodeRef>> PreservedVariables;
///
/// Do not use a std::vector. Some versions of libc++ apparently copy
/// instead of move on grow operations, and TrackingMDRef is expensive to
/// copy.
DenseMap<MDNode *, SmallVector<TrackingMDNodeRef, 1>> PreservedVariables;
DIBuilder(const DIBuilder &) = delete;
void operator=(const DIBuilder &) = delete;

7
lib/Bitcode/Reader/BitcodeReader.cpp
View File

@ -107,7 +107,12 @@ class BitcodeReaderMetadataList {
bool AnyFwdRefs;
unsigned MinFwdRef;
unsigned MaxFwdRef;
std::vector<TrackingMDRef> MetadataPtrs;
/// Array of metadata references.
///
/// Don't use std::vector here. Some versions of libc++ copy (instead of
/// move) on resize, and TrackingMDRef is very expensive to copy.
SmallVector<TrackingMDRef, 1> MetadataPtrs;
LLVMContext &Context;
public:

2
lib/IR/DIBuilder.cpp
View File

@ -614,7 +614,7 @@ DIGlobalVariable *DIBuilder::createTempGlobalVariableFwdDecl(
static DILocalVariable *createLocalVariable(
LLVMContext &VMContext,
DenseMap<MDNode *, std::vector<TrackingMDNodeRef>> &PreservedVariables,
DenseMap<MDNode *, SmallVector<TrackingMDNodeRef, 1>> &PreservedVariables,
DIScope *Scope, StringRef Name, unsigned ArgNo, DIFile *File,
unsigned LineNo, DIType *Ty, bool AlwaysPreserve, unsigned Flags) {
// FIXME: Why getNonCompileUnitScope()?