Fix the branch island handling to account for the other possible

forms: '.island2' and '.island.2'.  Also add more padding so that
we produce an island that takes several jumps.

Author: jimingham

lldb/source/Plugins/DynamicLoader/MacOSX-DYLD/DynamicLoaderDarwin.cpp

@@ -1030,10 +1030,15 @@ DynamicLoaderDarwin::GetStepThroughTrampolinePlan(Thread &thread,
           thread, load_addrs, stop_others);
     }
     // One more case we have to consider is "branch islands".  These are regular
-    // TEXT symbols but their names end in .island.  They are to allow arm64
-    // code to branch further than the size of the address slot allows.  We
-    // just need to single-instruction step in that case.
-    if (!thread_plan_sp && current_name.GetStringRef().ends_with(".island")) {
+    // TEXT symbols but their names end in .island plus maybe a .digit suffix.  
+    // They are to allow arm64 code to branch further than the size of the 
+    // address slot allows.  We just need to single-instruction step in that 
+    // case.
+    static const char *g_branch_island_pattern = "\\.island\\.?[0-9]*$";
+    static RegularExpression g_branch_island_regex(g_branch_island_pattern);
+
+    bool is_branch_island = g_branch_island_regex.Execute(current_name);
+    if (!thread_plan_sp && is_branch_island) {
       thread_plan_sp = std::make_shared<ThreadPlanStepInstruction>(
           thread,
           /* step_over= */ false, /* stop_others */ false, eVoteNoOpinion,

lldb/test/API/macosx/branch-islands/Makefile

@@ -3,11 +3,14 @@ CFLAGS_EXTRAS := -std=c99
 
 include Makefile.rules
 
-a.out: main.o padding1.o padding2.o foo.o
-	${CC} ${LDFLAGS} foo.o padding1.o padding2.o main.o -o a.out
+a.out: main.o padding1.o padding2.o padding3.o padding4.o foo.o
+	${CC} ${LDFLAGS} foo.o padding1.o padding2.o padding3.o padding4.o main.o -o a.out
 
-padding1.o: padding1.s
-	${CC} -c $(SRCDIR)/padding1.s
+%.o: $(SRCDIR)/%.s
+	${CC} -c $<
 
-padding2.o: padding2.s
-	${CC} -c $(SRCDIR)/padding2.s
+#padding1.o: padding1.s
+#	${CC} -c $(SRCDIR)/padding1.s
+
+#padding2.o: padding2.s
+#	${CC} -c $(SRCDIR)/padding2.s

lldb/test/API/macosx/branch-islands/padding1.s

@@ -1,3 +1,3 @@
 .text
-_junk1:
+_padding1:
 .space 120*1024*1024

lldb/test/API/macosx/branch-islands/padding2.s

@@ -1,3 +1,3 @@
 .text
-_junk2:
+_padding2:
 .space 120*1024*1024

lldb/test/API/macosx/branch-islands/padding3.s

@@ -0,0 +1,3 @@
+.text
+_padding3:
+.space 120*1024*1024

lldb/test/API/macosx/branch-islands/padding4.s

@@ -0,0 +1,3 @@
+.text
+_padding4:
+.space 120*1024*1024