Do not share a single unknown val# for all the live ranges merged into a physical sub-register live interval. When coalescer is merging in clobbered virtaul register live interval into a physical register live interval, give each virtual register val# a separate val# in the physical register live interval. Otherwise, the coalescer would have lost track of the definitions information it needs to make correct coalescing decisions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70026 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LiveInterval.cpp b/lib/CodeGen/LiveInterval.cpp
index 68d9ad4..39d6611 100644
--- a/lib/CodeGen/LiveInterval.cpp
+++ b/lib/CodeGen/LiveInterval.cpp
@@ -19,6 +19,7 @@
//===----------------------------------------------------------------------===//
#include "llvm/CodeGen/LiveInterval.h"
+#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallSet.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/Support/Streams.h"
@@ -567,20 +568,6 @@
}
}
-VNInfo *LiveInterval::getUnknownValNo(BumpPtrAllocator &VNInfoAllocator) {
- unsigned i = getNumValNums();
- if (i) {
- do {
- --i;
- VNInfo *VNI = getValNumInfo(i);
- if (VNI->def == ~0U && !VNI->copy &&
- !VNI->hasPHIKill && !VNI->redefByEC && VNI->kills.empty())
- return VNI;
- } while (i != 0);
- }
- return getNextValue(~0U, 0, VNInfoAllocator);
-}
-
/// MergeInClobberRanges - For any live ranges that are not defined in the
/// current interval, but are defined in the Clobbers interval, mark them
@@ -589,12 +576,19 @@
BumpPtrAllocator &VNInfoAllocator) {
if (Clobbers.empty()) return;
- // Find a value # to use for the clobber ranges. If there is already a value#
- // for unknown values, use it.
- VNInfo *ClobberValNo = getUnknownValNo(VNInfoAllocator);
-
+ DenseMap<VNInfo*, VNInfo*> ValNoMaps;
iterator IP = begin();
for (const_iterator I = Clobbers.begin(), E = Clobbers.end(); I != E; ++I) {
+ // For every val# in the Clobbers interval, create a new "unknown" val#.
+ VNInfo *ClobberValNo = 0;
+ DenseMap<VNInfo*, VNInfo*>::iterator VI = ValNoMaps.find(I->valno);
+ if (VI != ValNoMaps.end())
+ ClobberValNo = VI->second;
+ else {
+ ClobberValNo = getNextValue(~0U, 0, VNInfoAllocator);
+ ValNoMaps.insert(std::make_pair(I->valno, ClobberValNo));
+ }
+
bool Done = false;
unsigned Start = I->start, End = I->end;
// If a clobber range starts before an existing range and ends after
@@ -637,7 +631,7 @@
BumpPtrAllocator &VNInfoAllocator) {
// Find a value # to use for the clobber ranges. If there is already a value#
// for unknown values, use it.
- VNInfo *ClobberValNo = getUnknownValNo(VNInfoAllocator);
+ VNInfo *ClobberValNo = getNextValue(~0U, 0, VNInfoAllocator);
iterator IP = begin();
IP = std::upper_bound(IP, end(), Start);