Make first substantial checkin of my port of ARM constant islands code to Mips.

Before I just ported the shell of the pass. I've tried to keep everything
nearly identical to the ARM version. I think it will be very easy to eventually
merge these two and create a new more general pass that other targets can
use. I have some improvements I would like to make to allow pools to 
be shared across functions and some other things. When I'm all done we
can think about making a more general pass. More to be ported but the
basic mechanism works now almost as good as gcc mips16.

llvm-svn: 193509

1 files changed, 11 insertions, 0 deletions

diff --git a/llvm/lib/Target/Mips/MipsSubtarget.cpp b/llvm/lib/Target/Mips/MipsSubtarget.cpp
index 3a122706aa2..0a81072b085 100644
--- a/llvm/lib/Target/Mips/MipsSubtarget.cpp
+++ b/llvm/lib/Target/Mips/MipsSubtarget.cpp
@@ -53,6 +53,12 @@ Mips16HardFloat("mips16-hard-float", cl::NotHidden,
                 cl::desc("MIPS: mips16 hard float enable."),
                 cl::init(false));
 
+static cl::opt<bool>
+Mips16ConstantIslands(
+  "mips16-constant-islands", cl::Hidden,
+  cl::desc("MIPS: mips16 constant islands enable. experimental feature"),
+  cl::init(false));
+
 void MipsSubtarget::anchor() { }
 
 MipsSubtarget::MipsSubtarget(const std::string &TT, const std::string &CPU,
@@ -163,3 +169,8 @@ void MipsSubtarget::resetSubtarget(MachineFunction *MF) {
 bool MipsSubtarget::mipsSEUsesSoftFloat() const {
   return TM->Options.UseSoftFloat && !InMips16HardFloat;
 }
+
+bool MipsSubtarget::useConstantIslands() {
+  DEBUG(dbgs() << "use constant islands " << Mips16ConstantIslands << "\n");
+  return Mips16ConstantIslands;
+}