Cleanups.
Make things a little more efficient as suggested by Evan.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89489 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/RegAllocLinearScan.cpp b/lib/CodeGen/RegAllocLinearScan.cpp
index 708ecbe..4ff5129 100644
--- a/lib/CodeGen/RegAllocLinearScan.cpp
+++ b/lib/CodeGen/RegAllocLinearScan.cpp
@@ -87,6 +87,7 @@
// Initialize the queue to record recently-used registers.
if (NumRecentlyUsedRegs > 0)
RecentRegs.resize(NumRecentlyUsedRegs, 0);
+ RecentNext = RecentRegs.begin();
}
typedef std::pair<LiveInterval*, LiveInterval::iterator> IntervalPtr;
@@ -154,14 +155,16 @@
std::auto_ptr<Spiller> spiller_;
// The queue of recently-used registers.
- SmallVector<unsigned, 3> RecentRegs;
+ SmallVector<unsigned, 4> RecentRegs;
+ SmallVector<unsigned, 4>::iterator RecentNext;
// Record that we just picked this register.
void recordRecentlyUsed(unsigned reg) {
assert(reg != 0 && "Recently used register is NOREG!");
if (!RecentRegs.empty()) {
- std::copy(RecentRegs.begin() + 1, RecentRegs.end(), RecentRegs.begin());
- RecentRegs.back() = reg;
+ *RecentNext++ = reg;
+ if (RecentNext == RecentRegs.end())
+ RecentNext = RecentRegs.begin();
}
}