Instead of adding dependence edges between terminator instructions

and every other instruction in their blocks to keep the terminator
instructions at the end, teach the post-RA scheduler how to operate
on ranges of instructions, and exclude terminators from the range
of instructions that get scheduled.

Also, exclude mid-block labels, such as EH_LABEL instructions, and
schedule code before them separately from code after them. This
fixes problems with the post-RA scheduler moving code past
EH_LABELs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62366 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 10 insertions, 2 deletions

diff --git a/lib/CodeGen/PostRASchedulerList.cpp b/lib/CodeGen/PostRASchedulerList.cpp
index eef20b9386..7bf3b3c342 100644
--- a/lib/CodeGen/PostRASchedulerList.cpp
+++ b/lib/CodeGen/PostRASchedulerList.cpp
@@ -187,9 +187,17 @@ bool PostRAScheduler::runOnMachineFunction(MachineFunction &Fn) {
   // Loop over all of the basic blocks
   for (MachineFunction::iterator MBB = Fn.begin(), MBBe = Fn.end();
        MBB != MBBe; ++MBB) {
+    // Schedule each sequence of instructions not interrupted by a label
+    // or anything else that effectively needs to shut down scheduling.
+    MachineBasicBlock::iterator Current = MBB->begin(), End = MBB->end();
+    for (MachineBasicBlock::iterator MI = Current; MI != End; ++MI)
+      if (MI->getDesc().isTerminator() || MI->isLabel()) {
+        Scheduler.Run(0, MBB, Current, MI);
+        Scheduler.EmitSchedule();
+        Current = next(MI);
+      }
 
-    Scheduler.Run(0, MBB);
-
+    Scheduler.Run(0, MBB, Current, End);
     Scheduler.EmitSchedule();
   }