nicolas/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

It has finally happened. Spiller is now using live interval info.

Browse Source 
This fixes a very subtle bug. vr defined by an implicit_def is allowed overlap with any register since it doesn't actually modify anything. However, if it's used as a two-address use, its live range can be extended and it can be spilled. The spiller must take care not to emit a reload for the vn number that's defined by the implicit_def. This is both a correctness and performance issue.

llvm-svn: 69743
This commit is contained in:
Evan Cheng
2009-04-21 22:46:52 +00:00
parent 41b8694777
commit 1a99a5f501
7 changed files with 95 additions and 42 deletions
Download Patch File Download Diff File Expand all files Collapse all files

2
llvm/lib/CodeGen/RegAllocLinearScan.cpp
View File

@@ -345,7 +345,7 @@ bool RALinScan::runOnMachineFunction(MachineFunction &fn) {
linearScan();
// Rewrite spill code and update the PhysRegsUsed set.
spiller_->runOnMachineFunction(*mf_, *vrm_);
spiller_->runOnMachineFunction(*mf_, *vrm_, li_);
assert(unhandled_.empty() && "Unhandled live intervals remain!");
fixed_.clear();