Enable stack coloring by default.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52057 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LLVMTargetMachine.cpp b/lib/CodeGen/LLVMTargetMachine.cpp
index d3e8e49..1c8ce0a 100644
--- a/lib/CodeGen/LLVMTargetMachine.cpp
+++ b/lib/CodeGen/LLVMTargetMachine.cpp
@@ -38,10 +38,6 @@
EnableSinking("enable-sinking", cl::init(false), cl::Hidden,
cl::desc("Perform sinking on machine code"));
static cl::opt<bool>
-EnableStackColoring("stack-coloring",
- cl::init(false), cl::Hidden,
- cl::desc("Perform stack slot coloring"));
-static cl::opt<bool>
EnableLICM("machine-licm",
cl::init(false), cl::Hidden,
cl::desc("Perform loop-invariant code motion on machine code"));
@@ -103,8 +99,7 @@
PM.add(createRegisterAllocator());
// Perform stack slot coloring.
- if (EnableStackColoring)
- PM.add(createStackSlotColoringPass());
+ PM.add(createStackSlotColoringPass());
if (PrintMachineCode) // Print the register-allocated code
PM.add(createMachineFunctionPrinterPass(cerr));
@@ -240,8 +235,7 @@
PM.add(createRegisterAllocator());
// Perform stack slot coloring.
- if (EnableStackColoring)
- PM.add(createStackSlotColoringPass());
+ PM.add(createStackSlotColoringPass());
if (PrintMachineCode)
PM.add(createMachineFunctionPrinterPass(cerr));
diff --git a/lib/CodeGen/README.txt b/lib/CodeGen/README.txt
index a66fc9d..d5ddd21 100644
--- a/lib/CodeGen/README.txt
+++ b/lib/CodeGen/README.txt
@@ -197,3 +197,12 @@
which would eliminate a bunch of explicit predicates on them (e.g. no side
effects). Once this is in place, it would be even better to have tblgen
synthesize the various copy insertion/inspection methods in TargetInstrInfo.
+
+//===---------------------------------------------------------------------===//
+
+Stack coloring improvments:
+
+1. Do proper LiveStackAnalysis on all stack objects including those which are
+ not spill slots.
+2. Reorder objects to fill in gaps between objects.
+ e.g. 4, 1, <gap>, 4, 1, 1, 1, <gap>, 4 => 4, 1, 1, 1, 1, 4, 4