[Lldb-commits] [lldb] 661e404 - [LLDB] Fix SVE reginfo for sequential offset in g packet

[Muhammad Omair Javaid via lldb-commits]

Author: Muhammad Omair Javaid
Date: 2020-11-17T17:18:34+05:00
New Revision: 661e4040ac60b3df06b2495ea916302b35d9bac2

URL: https://github.com/llvm/llvm-project/commit/661e4040ac60b3df06b2495ea916302b35d9bac2
DIFF: https://github.com/llvm/llvm-project/commit/661e4040ac60b3df06b2495ea916302b35d9bac2.diff

LOG: [LLDB] Fix SVE reginfo for sequential offset in g packet

This moves in the direction of our effort to synchronize register descriptions
between LLDB and GDB xml description. We want to able to send registers in a
way that their offset fields can be re-constructed based on register sizes
in the increasing order of register number.

In context to Arm64 SVE, FPCR and FPSR are same registers in FPU regset and
SVE regset. Previously FPSR/FPCR offset was set at the end of SVE data
because Linux ptrace data placed FPCR and FPSR at the end of SVE register set.

Considering interoperability with other stubs like QEMU and that g packets
should generate register data in increasing order of register numbers. We
have to move FPCR/FPSR offset up to its original location according to
register numbering scheme of ARM64 registers with SVE registers included.

Reviewed By: labath

Differential Revision: https://reviews.llvm.org/D90741

Added: 
    

Modified: 
    lldb/source/Plugins/Process/Linux/NativeRegisterContextLinux_arm64.cpp
    lldb/source/Plugins/Process/Utility/RegisterInfoPOSIX_arm64.cpp
    lldb/source/Plugins/Process/elf-core/RegisterContextPOSIXCore_arm64.cpp

Removed: 
    


################################################################################
diff  --git a/lldb/source/Plugins/Process/Linux/NativeRegisterContextLinux_arm64.cpp b/lldb/source/Plugins/Process/Linux/NativeRegisterContextLinux_arm64.cpp
index 810bc8479742f..1fa87e13a0aac 100644
--- a/lldb/source/Plugins/Process/Linux/NativeRegisterContextLinux_arm64.cpp
+++ b/lldb/source/Plugins/Process/Linux/NativeRegisterContextLinux_arm64.cpp
@@ -1111,7 +1111,7 @@ uint32_t NativeRegisterContextLinux_arm64::CalculateSVEOffset(
     sve_reg_offset =
         SVE_PT_FPSIMD_OFFSET + (reg - GetRegisterInfo().GetRegNumSVEZ0()) * 16;
   } else if (m_sve_state == SVEState::Full) {
-    uint32_t sve_z0_offset = GetGPRSize() + 8;
+    uint32_t sve_z0_offset = GetGPRSize() + 16;
     sve_reg_offset =
         SVE_SIG_REGS_OFFSET + reg_info->byte_offset - sve_z0_offset;
   }

diff  --git a/lldb/source/Plugins/Process/Utility/RegisterInfoPOSIX_arm64.cpp b/lldb/source/Plugins/Process/Utility/RegisterInfoPOSIX_arm64.cpp
index 2e8335f23b65b..701c88c312586 100644
--- a/lldb/source/Plugins/Process/Utility/RegisterInfoPOSIX_arm64.cpp
+++ b/lldb/source/Plugins/Process/Utility/RegisterInfoPOSIX_arm64.cpp
@@ -288,8 +288,10 @@ RegisterInfoPOSIX_arm64::ConfigureVectorRegisterInfos(uint32_t sve_vq) {
 
     uint32_t offset = SVE_REGS_DEFAULT_OFFSET_LINUX;
 
-    reg_info_ref[sve_vg].byte_offset = offset;
-    offset += reg_info_ref[sve_vg].byte_size;
+    reg_info_ref[fpu_fpsr].byte_offset = offset;
+    reg_info_ref[fpu_fpcr].byte_offset = offset + 4;
+    reg_info_ref[sve_vg].byte_offset = offset + 8;
+    offset += 16;
 
     // Update Z registers size and offset
     uint32_t s_reg_base = fpu_s0;
@@ -314,8 +316,7 @@ RegisterInfoPOSIX_arm64::ConfigureVectorRegisterInfos(uint32_t sve_vq) {
       offset += reg_info_ref[it].byte_size;
     }
 
-    reg_info_ref[fpu_fpsr].byte_offset = offset;
-    reg_info_ref[fpu_fpcr].byte_offset = offset + 4;
+    m_per_vq_reg_infos[sve_vq] = reg_info_ref;
   }
 
   m_register_info_p = reg_info_ref.data();

diff  --git a/lldb/source/Plugins/Process/elf-core/RegisterContextPOSIXCore_arm64.cpp b/lldb/source/Plugins/Process/elf-core/RegisterContextPOSIXCore_arm64.cpp
index c19fe88aa6639..129a887a550cf 100644
--- a/lldb/source/Plugins/Process/elf-core/RegisterContextPOSIXCore_arm64.cpp
+++ b/lldb/source/Plugins/Process/elf-core/RegisterContextPOSIXCore_arm64.cpp
@@ -89,7 +89,7 @@ uint32_t RegisterContextCorePOSIX_arm64::CalculateSVEOffset(
     const uint32_t reg = reg_info->kinds[lldb::eRegisterKindLLDB];
     sve_reg_offset = sve::ptrace_fpsimd_offset + (reg - GetRegNumSVEZ0()) * 16;
   } else if (m_sve_state == SVEState::Full) {
-    uint32_t sve_z0_offset = GetGPRSize() + 8;
+    uint32_t sve_z0_offset = GetGPRSize() + 16;
     sve_reg_offset =
         sve::SigRegsOffset() + reg_info->byte_offset - sve_z0_offset;
   }