Index: Makefile
===================================================================
--- Makefile
+++ Makefile
@@ -34,6 +34,7 @@
 CPP.Flags += -I$(PROJ_OBJ_DIR)/$(LLDB_LEVEL)/include
 CPP.Flags += -I$(LLVM_SRC_ROOT)/tools/clang/include
 CPP.Flags += -I$(LLVM_OBJ_ROOT)/tools/clang/include
+CPP.Flags += -I$(LLVM_OBJ_ROOT)/lib/Target/ARM
 CPP.Flags += -I$(PROJ_SRC_DIR)/$(LLDB_LEVEL)/source
 CPP.Flags += -I$(PROJ_SRC_DIR)/$(LLDB_LEVEL)/source/Utility
 CPP.Flags += -I$(PROJ_SRC_DIR)/$(LLDB_LEVEL)/source/Plugins/Process/Utility
Index: include/lldb/Core/ArchSpec.h
===================================================================
--- include/lldb/Core/ArchSpec.h
+++ include/lldb/Core/ArchSpec.h
@@ -581,6 +581,22 @@
         m_flags = flags;
     }
 
+    //------------------------------------------------------------------
+    /// Detect whether this architecture uses thumb code exclusively
+    ///
+    /// Some embedded ARM chips (e.g. the ARM Cortex M0-7 line) can
+    /// only execute the Thumb instructions, never Arm.  We should normally
+    /// pick up arm/thumbness from their the processor status bits (cpsr/xpsr)
+    /// or hints on each function - but when doing bare-boards low level
+    /// debugging (especially common with these embedded processors), we may
+    /// not have those things easily accessible.
+    ///
+    /// @return true if this is an arm ArchSpec which can only execute Thumb
+    ///         instructions
+    //------------------------------------------------------------------
+    bool
+    IsAlwaysThumbInstructions () const;
+
 protected:
     bool
     IsEqualTo (const ArchSpec& rhs, bool exact_match) const;
Index: lldb.xcodeproj/project.pbxproj
===================================================================
--- lldb.xcodeproj/project.pbxproj
+++ lldb.xcodeproj/project.pbxproj
@@ -713,8 +713,8 @@
 		6D95DC001B9DC057000E318A /* DIERef.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 6D95DBFD1B9DC057000E318A /* DIERef.cpp */; };
 		6D95DC011B9DC057000E318A /* HashedNameToDIE.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 6D95DBFE1B9DC057000E318A /* HashedNameToDIE.cpp */; };
 		6D95DC021B9DC057000E318A /* SymbolFileDWARFDwo.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 6D95DBFF1B9DC057000E318A /* SymbolFileDWARFDwo.cpp */; };
-		6D9AB3DD1BB2B74E003F2289 /* TypeMap.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 6D9AB3DC1BB2B74E003F2289 /* TypeMap.cpp */; };
 		6D99A3631BBC2F3200979793 /* ArmUnwindInfo.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 6D99A3621BBC2F3200979793 /* ArmUnwindInfo.cpp */; };
+		6D9AB3DD1BB2B74E003F2289 /* TypeMap.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 6D9AB3DC1BB2B74E003F2289 /* TypeMap.cpp */; };
 		8C2D6A53197A1EAF006989C9 /* MemoryHistory.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 8C2D6A52197A1EAF006989C9 /* MemoryHistory.cpp */; };
 		8C2D6A5E197A250F006989C9 /* MemoryHistoryASan.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 8C2D6A5A197A1FDC006989C9 /* MemoryHistoryASan.cpp */; };
 		8CCB017E19BA28A80009FD44 /* ThreadCollection.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 8CCB017A19BA283D0009FD44 /* ThreadCollection.cpp */; };
@@ -2407,10 +2407,10 @@
 		6D95DBFF1B9DC057000E318A /* SymbolFileDWARFDwo.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = SymbolFileDWARFDwo.cpp; sourceTree = "<group>"; };
 		6D95DC031B9DC06F000E318A /* DIERef.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = DIERef.h; sourceTree = "<group>"; };
 		6D95DC041B9DC06F000E318A /* SymbolFileDWARFDwo.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; path = SymbolFileDWARFDwo.h; sourceTree = "<group>"; };
-		6D9AB3DC1BB2B74E003F2289 /* TypeMap.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = TypeMap.cpp; path = source/Symbol/TypeMap.cpp; sourceTree = "<group>"; };
-		6D9AB3DE1BB2B76B003F2289 /* TypeMap.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = TypeMap.h; path = include/lldb/Symbol/TypeMap.h; sourceTree = "<group>"; };
 		6D99A3611BBC2F1600979793 /* ArmUnwindInfo.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = ArmUnwindInfo.h; path = include/lldb/Symbol/ArmUnwindInfo.h; sourceTree = "<group>"; };
 		6D99A3621BBC2F3200979793 /* ArmUnwindInfo.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = ArmUnwindInfo.cpp; path = source/Symbol/ArmUnwindInfo.cpp; sourceTree = "<group>"; };
+		6D9AB3DC1BB2B74E003F2289 /* TypeMap.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = TypeMap.cpp; path = source/Symbol/TypeMap.cpp; sourceTree = "<group>"; };
+		6D9AB3DE1BB2B76B003F2289 /* TypeMap.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = TypeMap.h; path = include/lldb/Symbol/TypeMap.h; sourceTree = "<group>"; };
 		8C2D6A52197A1EAF006989C9 /* MemoryHistory.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = MemoryHistory.cpp; path = source/Target/MemoryHistory.cpp; sourceTree = "<group>"; };
 		8C2D6A54197A1EBE006989C9 /* MemoryHistory.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = MemoryHistory.h; path = include/lldb/Target/MemoryHistory.h; sourceTree = "<group>"; };
 		8C2D6A5A197A1FDC006989C9 /* MemoryHistoryASan.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = MemoryHistoryASan.cpp; sourceTree = "<group>"; };
@@ -7435,7 +7435,7 @@
 					Foundation,
 				);
 				PRODUCT_NAME = LLDB;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 				VERSIONING_SYSTEM = "apple-generic";
 			};
 			name = Debug;
@@ -7508,7 +7508,7 @@
 					Foundation,
 				);
 				PRODUCT_NAME = LLDB;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 				VERSIONING_SYSTEM = "apple-generic";
 			};
 			name = Release;
@@ -7609,7 +7609,7 @@
 				PRODUCT_NAME = "lib$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
 				STANDARD_C_PLUS_PLUS_LIBRARY_TYPE = static;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 				VERSIONING_SYSTEM = "apple-generic";
 			};
 			name = Debug;
@@ -7654,7 +7654,7 @@
 				PRODUCT_NAME = "lib$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
 				STANDARD_C_PLUS_PLUS_LIBRARY_TYPE = static;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 				VERSIONING_SYSTEM = "apple-generic";
 			};
 			name = Release;
@@ -7699,7 +7699,7 @@
 				PRODUCT_NAME = "lib$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
 				STANDARD_C_PLUS_PLUS_LIBRARY_TYPE = static;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 				VERSIONING_SYSTEM = "apple-generic";
 			};
 			name = BuildAndIntegration;
@@ -7900,7 +7900,7 @@
 				);
 				PRODUCT_NAME = LLDB;
 				STRIP_INSTALLED_PRODUCT = YES;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 				VERSIONING_SYSTEM = "apple-generic";
 			};
 			name = BuildAndIntegration;
@@ -7937,7 +7937,7 @@
 				);
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SDKROOT = macosx;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 				VERSIONING_SYSTEM = "apple-generic";
 			};
 			name = Debug;
@@ -7974,7 +7974,7 @@
 				);
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SDKROOT = macosx;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 				VERSIONING_SYSTEM = "apple-generic";
 			};
 			name = DebugClang;
@@ -8007,7 +8007,7 @@
 				);
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SDKROOT = macosx;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 				VERSIONING_SYSTEM = "apple-generic";
 			};
 			name = Release;
@@ -8055,7 +8055,7 @@
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SDKROOT = macosx;
 				STRIP_INSTALLED_PRODUCT = YES;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 				VERSIONING_SYSTEM = "apple-generic";
 			};
 			name = BuildAndIntegration;
@@ -8205,7 +8205,7 @@
 				);
 				PRODUCT_NAME = "lldb-server";
 				SKIP_INSTALL = YES;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 			};
 			name = Debug;
 		};
@@ -8278,7 +8278,7 @@
 				);
 				PRODUCT_NAME = "lldb-server";
 				SKIP_INSTALL = YES;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 			};
 			name = Release;
 		};
@@ -8352,7 +8352,7 @@
 				PRODUCT_NAME = "lldb-server";
 				SKIP_INSTALL = YES;
 				STRIP_INSTALLED_PRODUCT = YES;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 			};
 			name = BuildAndIntegration;
 		};
@@ -8627,7 +8627,7 @@
 					Foundation,
 				);
 				PRODUCT_NAME = LLDB;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 				VERSIONING_SYSTEM = "apple-generic";
 			};
 			name = DebugClang;
@@ -8685,7 +8685,7 @@
 				PRODUCT_NAME = "lib$(TARGET_NAME)";
 				SKIP_INSTALL = YES;
 				STANDARD_C_PLUS_PLUS_LIBRARY_TYPE = static;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 				VERSIONING_SYSTEM = "apple-generic";
 			};
 			name = DebugClang;
@@ -8761,7 +8761,7 @@
 				);
 				PRODUCT_NAME = "lldb-server";
 				SKIP_INSTALL = YES;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 			};
 			name = DebugClang;
 		};
@@ -8919,7 +8919,7 @@
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SDKROOT = macosx;
 				SKIP_INSTALL = YES;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 			};
 			name = Debug;
 		};
@@ -8988,7 +8988,7 @@
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SDKROOT = macosx;
 				SKIP_INSTALL = YES;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 			};
 			name = DebugClang;
 		};
@@ -9054,7 +9054,7 @@
 				PRODUCT_NAME = "$(TARGET_NAME)";
 				SDKROOT = macosx;
 				SKIP_INSTALL = YES;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 			};
 			name = Release;
 		};
@@ -9123,7 +9123,7 @@
 				SDKROOT = macosx;
 				SKIP_INSTALL = YES;
 				STRIP_INSTALLED_PRODUCT = YES;
-				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include";
+				USER_HEADER_SEARCH_PATHS = "$(SRCROOT)/include $(SRCROOT)/source $(LLVM_SOURCE_DIR)/include $(LLVM_SOURCE_DIR)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/tools/clang/include $(LLVM_BUILD_DIR)/$(LLVM_BUILD_DIR_ARCH)/lib/Target/ARM";
 			};
 			name = BuildAndIntegration;
 		};
Index: source/Core/ArchSpec.cpp
===================================================================
--- source/Core/ArchSpec.cpp
+++ source/Core/ArchSpec.cpp
@@ -32,6 +32,11 @@
 #include "Plugins/Process/Utility/ARMDefines.h"
 #include "Plugins/Process/Utility/InstructionUtils.h"
 
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/MC/MCSubtargetInfo.h"
+#include "llvm/../../lib/Target/ARM/ARMGenRegisterInfo.inc"
+#include "llvm/../../lib/Target/ARM/ARMFeatures.h"
+
 using namespace lldb;
 using namespace lldb_private;
 
@@ -850,6 +855,19 @@
         GetTriple().setOS(other.GetTriple().getOS());
     if (GetTriple().getArch() == llvm::Triple::UnknownArch)
         GetTriple().setArch(other.GetTriple().getArch());
+
+    // If this and other are both arm ArchSpecs and this ArchSpec is a generic "some kind of arm"
+    // spec but the other ArchSpec is a specific arm core, adopt the specific arm core.
+    if (GetTriple().getArch() == llvm::Triple::arm
+        && other.GetTriple().getArch() == llvm::Triple::arm
+        && IsCompatibleMatch (other)
+        && GetCore() == ArchSpec::eCore_arm_generic
+        && other.GetCore() != ArchSpec::eCore_arm_generic)
+    {
+        m_core = other.GetCore();
+        CoreUpdated (true);
+    }
+
     if (GetTriple().getEnvironment() == llvm::Triple::UnknownEnvironment)
         GetTriple().setEnvironment(other.GetTriple().getEnvironment());
 }
@@ -1444,3 +1462,22 @@
         return StopInfoOverrideCallbackTypeARM;
     return NULL;
 }
+
+bool
+ArchSpec::IsAlwaysThumbInstructions () const
+{
+    std::string Error;
+    if (GetTriple().getArch() == llvm::Triple::arm || GetTriple().getArch() == llvm::Triple::thumb)
+    {
+        std::string triple (GetTriple().getTriple());
+        const char *cpu = "";
+        const char *features_str = "";
+        const llvm::Target *curr_target = llvm::TargetRegistry::lookupTarget(triple.c_str(), Error);
+        std::unique_ptr<llvm::MCSubtargetInfo> subtarget_info_up (curr_target->createMCSubtargetInfo(triple.c_str(), cpu, features_str));
+        if (subtarget_info_up->getFeatureBits()[llvm::ARM::FeatureNoARM])
+        {
+            return true;
+        }
+    }
+    return false;
+}
Index: source/Core/Disassembler.cpp
===================================================================
--- source/Core/Disassembler.cpp
+++ source/Core/Disassembler.cpp
@@ -1270,10 +1270,7 @@
     // If this is an arm variant that can only include thumb (T16, T32)
     // instructions, force the arch triple to be "thumbv.." instead of
     // "armv..."
-    if ((arch.GetTriple().getArch() == llvm::Triple::arm || arch.GetTriple().getArch() == llvm::Triple::thumb)
-        && (arch.GetCore() == ArchSpec::Core::eCore_arm_armv7m
-            || arch.GetCore() == ArchSpec::Core::eCore_arm_armv7em
-            || arch.GetCore() == ArchSpec::Core::eCore_arm_armv6m))
+    if (arch.IsAlwaysThumbInstructions())
     {
         std::string thumb_arch_name (arch.GetTriple().getArchName().str());
         // Replace "arm" with "thumb" so we get all thumb variants correct
Index: source/Plugins/Disassembler/llvm/DisassemblerLLVMC.cpp
===================================================================
--- source/Plugins/Disassembler/llvm/DisassemblerLLVMC.cpp
+++ source/Plugins/Disassembler/llvm/DisassemblerLLVMC.cpp
@@ -673,18 +673,8 @@
 
     const char *triple_str = triple.getTriple().c_str();
 
-    // v. https://en.wikipedia.org/wiki/ARM_Cortex-M#Silicon_customization
-    // 
-    // Cortex-M3 devices (e.g. armv7m) can only execute thumb (T2) instructions,
-    // so hardcode the primary disassembler to thumb mode.  Same for Cortex-M4 (armv7em).
-    //
-    // Handle the Cortex-M0 (armv6m) the same; the ISA is a subset of the T and T32
-    // instructions defined in ARMv7-A.
-
-    if ((triple.getArch() == llvm::Triple::arm || triple.getArch() == llvm::Triple::thumb)
-        && (arch.GetCore() == ArchSpec::Core::eCore_arm_armv7m
-            || arch.GetCore() == ArchSpec::Core::eCore_arm_armv7em
-            || arch.GetCore() == ArchSpec::Core::eCore_arm_armv6m))
+    // ARM Cortex M0-M7 devices only execute thumb instructions
+    if (arch.IsAlwaysThumbInstructions ())
     {
         triple_str = thumb_arch.GetTriple().getTriple().c_str();
     }
Index: source/Plugins/Instruction/ARM/EmulateInstructionARM.cpp
===================================================================
--- source/Plugins/Instruction/ARM/EmulateInstructionARM.cpp
+++ source/Plugins/Instruction/ARM/EmulateInstructionARM.cpp
@@ -12992,8 +12992,10 @@
 {
     if (EmulateInstruction::SetInstruction (insn_opcode, inst_addr, target))
     {
-        if (m_arch.GetTriple().getArch() == llvm::Triple::thumb)
+        if (m_arch.GetTriple().getArch() == llvm::Triple::thumb || m_arch.IsAlwaysThumbInstructions ())
+        {
             m_opcode_mode = eModeThumb;
+        }
         else
         {
             AddressClass addr_class = inst_addr.GetAddressClass();
@@ -13028,7 +13030,7 @@
             read_inst_context.type = eContextReadOpcode;
             read_inst_context.SetNoArgs ();
                   
-            if (m_opcode_cpsr & MASK_CPSR_T)
+            if (m_opcode_cpsr & MASK_CPSR_T || m_arch.IsAlwaysThumbInstructions())
             {
                 m_opcode_mode = eModeThumb;
                 uint32_t thumb_opcode = MemARead(read_inst_context, pc, 2, 0, &success);
@@ -13657,19 +13659,17 @@
     }
     test_opcode = value_sp->GetUInt64Value ();
 
-    if (arch.GetTriple().getArch() == llvm::Triple::arm)
-    {
-        m_opcode_mode = eModeARM;
-        m_opcode.SetOpcode32 (test_opcode, GetByteOrder());
-    }
-    else if (arch.GetTriple().getArch() == llvm::Triple::thumb)
+    if (arch.GetTriple().getArch() == llvm::Triple::thumb || arch.IsAlwaysThumbInstructions ())
     {
         m_opcode_mode = eModeThumb;
         if (test_opcode < 0x10000)
             m_opcode.SetOpcode16 (test_opcode, GetByteOrder());
         else
             m_opcode.SetOpcode32 (test_opcode, GetByteOrder());
-
+    } else if (arch.GetTriple().getArch() == llvm::Triple::arm)
+    {
+        m_opcode_mode = eModeARM;
+        m_opcode.SetOpcode32 (test_opcode, GetByteOrder());
     }
     else
     {