Add initial support for ARMv7M subtarget and cortex-m3 cpu. Patch by
Jordy <snhjordy@gmail.com>.

Followup patches will add some tests and adjust to use Subtarget features
for the instructions.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103119 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp
index c8a8ac8..c1d2d3a 100644
--- a/lib/Target/ARM/ARMISelLowering.cpp
+++ b/lib/Target/ARM/ARMISelLowering.cpp
@@ -363,8 +363,11 @@
     setOperationAction(ISD::BSWAP, MVT::i32, Expand);
 
   // These are expanded into libcalls.
-  setOperationAction(ISD::SDIV,  MVT::i32, Expand);
-  setOperationAction(ISD::UDIV,  MVT::i32, Expand);
+  if (!Subtarget->hasV7MOps()) {
+    // v7M has a hardware divider
+    setOperationAction(ISD::SDIV,  MVT::i32, Expand);
+    setOperationAction(ISD::UDIV,  MVT::i32, Expand);
+  }
   setOperationAction(ISD::SREM,  MVT::i32, Expand);
   setOperationAction(ISD::UREM,  MVT::i32, Expand);
   setOperationAction(ISD::SDIVREM, MVT::i32, Expand);
@@ -390,7 +393,7 @@
   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32, Expand);
   setOperationAction(ISD::MEMBARRIER,         MVT::Other, Custom);
 
-  if (!Subtarget->hasV6Ops() && !Subtarget->isThumb2()) {
+  if (!Subtarget->hasV6Ops() && !Subtarget->isThumb2() || Subtarget->hasV7MOps()) {
     setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16, Expand);
     setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8,  Expand);
   }