Once we have a way to fold spill code reloads into instructions, we have a way to use it. :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11517 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/RegAllocLocal.cpp b/lib/CodeGen/RegAllocLocal.cpp
index de12c6a..dc375cc 100644
--- a/lib/CodeGen/RegAllocLocal.cpp
+++ b/lib/CodeGen/RegAllocLocal.cpp
@@ -487,9 +487,24 @@
return MI;
}
- unsigned PhysReg = getReg(MBB, MI, VirtReg);
-
+ // Otherwise, we need to fold it into the current instruction, or reload it.
+ // If we have registers available to hold the value, use them.
const TargetRegisterClass *RC = MF->getSSARegMap()->getRegClass(VirtReg);
+ unsigned PhysReg = getFreeReg(RC);
+
+ if (PhysReg == 0) { // No registers available...
+ /// If we can fold this spill into this instruction, do so now.
+ if (0) {
+ // TODO
+ return MI;
+ }
+
+ // It looks like we can't fold this virtual register load into this
+ // instruction. Force some poor hapless value out of the register file to
+ // make room for the new register, and reload it.
+ PhysReg = getReg(MBB, MI, VirtReg);
+ }
+
int FrameIndex = getStackSpaceFor(VirtReg, RC);
markVirtRegModified(VirtReg, false); // Note that this reg was just reloaded