DynamicRegisterInfo calculate offsets in separate function

This patch pull offset calculation logic out of DynamicRegisterInfo::Finalize
into a separate function. We are going to call this function whenever we
update SVE register sizes.

Reviewed By: labath

Differential Revision: https://reviews.llvm.org/D94008

Author: omjavaid

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

@@ -442,28 +442,6 @@ void DynamicRegisterInfo::Finalize(const ArchSpec &arch) {
     m_sets[set].registers = m_set_reg_nums[set].data();
   }
 
-  // We are going to create a map between remote (eRegisterKindProcessPlugin)
-  // and local (eRegisterKindLLDB) register numbers. This map will give us
-  // remote register numbers in increasing order for offset calculation.
-  std::map<uint32_t, uint32_t> remote_to_local_regnum_map;
-  for (const auto &reg : m_regs)
-    remote_to_local_regnum_map[reg.kinds[eRegisterKindProcessPlugin]] =
-        reg.kinds[eRegisterKindLLDB];
-
-  // At this stage we manually calculate g/G packet offsets of all primary
-  // registers, only if target XML or qRegisterInfo packet did not send
-  // an offset explicitly.
-  uint32_t reg_offset = 0;
-  for (auto const &regnum_pair : remote_to_local_regnum_map) {
-    if (m_regs[regnum_pair.second].byte_offset == LLDB_INVALID_INDEX32 &&
-        m_regs[regnum_pair.second].value_regs == nullptr) {
-      m_regs[regnum_pair.second].byte_offset = reg_offset;
-
-      reg_offset = m_regs[regnum_pair.second].byte_offset +
-                   m_regs[regnum_pair.second].byte_size;
-    }
-  }
-
   // sort and unique all value registers and make sure each is terminated with
   // LLDB_INVALID_REGNUM
 
@@ -485,24 +463,10 @@ void DynamicRegisterInfo::Finalize(const ArchSpec &arch) {
   // Now update all value_regs with each register info as needed
   const size_t num_regs = m_regs.size();
   for (size_t i = 0; i < num_regs; ++i) {
-    if (m_value_regs_map.find(i) != m_value_regs_map.end()) {
+    if (m_value_regs_map.find(i) != m_value_regs_map.end())
       m_regs[i].value_regs = m_value_regs_map[i].data();
-      // Assign a valid offset to all pseudo registers if not assigned by stub.
-      // Pseudo registers with value_regs list populated will share same offset
-      // as that of their corresponding primary register in value_regs list.
-      if (m_regs[i].byte_offset == LLDB_INVALID_INDEX32) {
-        uint32_t value_regnum = m_regs[i].value_regs[0];
-        if (value_regnum != LLDB_INVALID_INDEX32)
-          m_regs[i].byte_offset =
-              GetRegisterInfoAtIndex(remote_to_local_regnum_map[value_regnum])
-                  ->byte_offset;
-      }
-    } else
+    else
       m_regs[i].value_regs = nullptr;
-
-    reg_offset = m_regs[i].byte_offset + m_regs[i].byte_size;
-    if (m_reg_data_byte_size < reg_offset)
-      m_reg_data_byte_size = reg_offset;
   }
 
   // Expand all invalidation dependencies
@@ -648,6 +612,55 @@ void DynamicRegisterInfo::Finalize(const ArchSpec &arch) {
       break;
     }
   }
+
+  // At this stage call ConfigureOffsets to calculate register offsets for
+  // targets supporting dynamic offset calculation. It also calculates
+  // total byte size of register data.
+  ConfigureOffsets();
+}
+
+void DynamicRegisterInfo::ConfigureOffsets() {
+  // We are going to create a map between remote (eRegisterKindProcessPlugin)
+  // and local (eRegisterKindLLDB) register numbers. This map will give us
+  // remote register numbers in increasing order for offset calculation.
+  std::map<uint32_t, uint32_t> remote_to_local_regnum_map;
+  for (const auto &reg : m_regs)
+    remote_to_local_regnum_map[reg.kinds[eRegisterKindProcessPlugin]] =
+        reg.kinds[eRegisterKindLLDB];
+
+  // At this stage we manually calculate g/G packet offsets of all primary
+  // registers, only if target XML or qRegisterInfo packet did not send
+  // an offset explicitly.
+  uint32_t reg_offset = 0;
+  for (auto const &regnum_pair : remote_to_local_regnum_map) {
+    if (m_regs[regnum_pair.second].byte_offset == LLDB_INVALID_INDEX32 &&
+        m_regs[regnum_pair.second].value_regs == nullptr) {
+      m_regs[regnum_pair.second].byte_offset = reg_offset;
+
+      reg_offset = m_regs[regnum_pair.second].byte_offset +
+                   m_regs[regnum_pair.second].byte_size;
+    }
+  }
+
+  // Now update all value_regs with each register info as needed
+  for (auto &reg : m_regs) {
+    if (reg.value_regs != nullptr) {
+      // Assign a valid offset to all pseudo registers if not assigned by stub.
+      // Pseudo registers with value_regs list populated will share same offset
+      // as that of their corresponding primary register in value_regs list.
+      if (reg.byte_offset == LLDB_INVALID_INDEX32) {
+        uint32_t value_regnum = reg.value_regs[0];
+        if (value_regnum != LLDB_INVALID_INDEX32)
+          reg.byte_offset =
+              GetRegisterInfoAtIndex(remote_to_local_regnum_map[value_regnum])
+                  ->byte_offset;
+      }
+    }
+
+    reg_offset = reg.byte_offset + reg.byte_size;
+    if (m_reg_data_byte_size < reg_offset)
+      m_reg_data_byte_size = reg_offset;
+  }
 }
 
 bool DynamicRegisterInfo::IsReconfigurable() { return m_is_reconfigurable; }

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

@@ -82,6 +82,8 @@ class DynamicRegisterInfo {
 
   void MoveFrom(DynamicRegisterInfo &&info);
 
+  void ConfigureOffsets();
+
   reg_collection m_regs;
   set_collection m_sets;
   set_reg_num_collection m_set_reg_nums;