Do in fact need adjustbreakpoint

Author: DavidSpickett

lldb/source/Plugins/Process/Utility/NativeRegisterContextDBReg.cpp

@@ -48,19 +48,9 @@ uint32_t NativeRegisterContextDBReg::SetHardwareBreakpoint(lldb::addr_t addr,
     return LLDB_INVALID_INDEX32;
 
   uint32_t control_value = MakeBreakControlValue(size);
-
-  // LLDB does this before making the request, but other clients may not.
-  switch (size) {
-  case 2:
-    addr &= ~1;
-    break;
-  case 4:
-    addr &= ~3;
-    break;
-  default:
-    // ValidateBreakpoint should have rejected this.
-    llvm_unreachable("Invalid breakpoint size.");
-  }
+  auto details = AdjustBreakpoint({size, addr});
+  size = details.size;
+  addr = details.addr;
 
   // Iterate over stored breakpoints and find a free bp_index
   uint32_t bp_index = LLDB_INVALID_INDEX32;

lldb/source/Plugins/Process/Utility/NativeRegisterContextDBReg.h

@@ -87,6 +87,12 @@ class NativeRegisterContextDBReg
   };
   virtual std::optional<WatchpointDetails>
   AdjustWatchpoint(const WatchpointDetails &details) = 0;
+
+  using BreakpointDetails = WatchpointDetails;
+  virtual BreakpointDetails AdjustBreakpoint(const BreakpointDetails &details) {
+    return details;
+  }
+
   virtual uint32_t MakeBreakControlValue(size_t size) = 0;
   virtual uint32_t MakeWatchControlValue(size_t size, uint32_t watch_flags) = 0;
   virtual uint32_t GetWatchpointSize(uint32_t wp_index) = 0;

lldb/source/Plugins/Process/Utility/NativeRegisterContextDBReg_arm.cpp

@@ -58,6 +58,27 @@ NativeRegisterContextDBReg_arm::AdjustWatchpoint(
   return WatchpointDetails{size, addr};
 }
 
+NativeRegisterContextDBReg::BreakpointDetails
+NativeRegisterContextDBReg_arm::AdjustBreakpoint(
+    const BreakpointDetails &details) {
+  BreakpointDetails bd = details;
+  // Use size to get a hint of arm vs thumb modes.
+  // LLDB usually aligns this client side, but other clients may not.
+  switch (bd.size) {
+  case 2:
+    bd.addr &= ~1;
+    break;
+  case 4:
+    bd.addr &= ~3;
+    break;
+  default:
+    // We assume that ValidateBreakpoint would have caught this earlier.
+    llvm_unreachable("Invalid breakpoint size!");
+  }
+
+  return bd;
+}
+
 uint32_t NativeRegisterContextDBReg_arm::MakeBreakControlValue(size_t size) {
   switch (size) {
   case 2:

lldb/source/Plugins/Process/Utility/NativeRegisterContextDBReg_arm.h

@@ -24,6 +24,8 @@ class NativeRegisterContextDBReg_arm : public NativeRegisterContextDBReg {
   std::optional<WatchpointDetails>
   AdjustWatchpoint(const WatchpointDetails &details) override;
 
+  BreakpointDetails AdjustBreakpoint(const BreakpointDetails &details) override;
+
   uint32_t MakeBreakControlValue(size_t size) override;
 
   uint32_t MakeWatchControlValue(size_t size, uint32_t watch_flags) override;