Avoid assigning esp (or ebp for framepointer-using frames) in Om1.

src/IceTargetLoweringX8632.cpp

Index: src/IceTargetLoweringX8632.cpp
diff --git a/src/IceTargetLoweringX8632.cpp b/src/IceTargetLoweringX8632.cpp
index 7630d37624bdd787fcc3f6ce7b2b69913c4fb210..569fd9e126f124431f618ba242ee52ac319efd16 100644
--- a/src/IceTargetLoweringX8632.cpp
+++ b/src/IceTargetLoweringX8632.cpp
@@ -2569,7 +2569,11 @@ void TargetX8632::postLower() {
   if (Ctx->getOptLevel() != Opt_m1)
     return;
   // TODO: Avoid recomputing WhiteList every instruction.
-  llvm::SmallBitVector WhiteList = getRegisterSet(RegSet_All, RegSet_None);
+  RegSetMask RegInclude = RegSet_All;
+  RegSetMask RegExclude = RegSet_None;
+  if (hasFramePointer())
+    RegExclude |= RegSet_FramePointer;
+  llvm::SmallBitVector WhiteList = getRegisterSet(RegInclude, RegExclude);
   // Make one pass to black-list pre-colored registers.  TODO: If
   // there was some prior register allocation pass that made register
   // assignments, those registers need to be black-listed here as