[Lldb-commits] [PATCH] D137519: [LLDB][LoongArch] Add LoongArch software breakpoint trap code

[Tiezhu Yang via Phabricator via lldb-commits]

seehearfeel created this revision.
seehearfeel added reviewers: SixWeining, wangleiat, xen0n, xry111, MaskRay, DavidSpickett.
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Take LoongArch "break" instruction as breakpoint trap code, so
our breakpoint works as expected now.

By the way, LoongArch doesn't support hardware single stepping
yet in upstream Linux, ptrace(PTRACE_SINGLESTEP) returns -EIO
now, a software implementation may come in future commit.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D137519

Files:
  lldb/source/Host/common/NativeProcessProtocol.cpp
  lldb/source/Target/Platform.cpp


Index: lldb/source/Target/Platform.cpp
===================================================================
--- lldb/source/Target/Platform.cpp
+++ lldb/source/Target/Platform.cpp
@@ -1939,6 +1939,14 @@
     }
   } break;
 
+  case llvm::Triple::loongarch32:
+  case llvm::Triple::loongarch64: {
+    static const uint8_t g_loongarch_opcode[] = {0x05, 0x00, 0x2a,
+                                                 0x00}; // break
+    trap_opcode = g_loongarch_opcode;
+    trap_opcode_size = sizeof(g_loongarch_opcode);
+  } break;
+
   default:
     return 0;
   }
Index: lldb/source/Host/common/NativeProcessProtocol.cpp
===================================================================
--- lldb/source/Host/common/NativeProcessProtocol.cpp
+++ lldb/source/Host/common/NativeProcessProtocol.cpp
@@ -507,6 +507,7 @@
   static const uint8_t g_ppcle_opcode[] = {0x08, 0x00, 0xe0, 0x7f}; // trap
   static const uint8_t g_riscv_opcode[] = {0x73, 0x00, 0x10, 0x00}; // ebreak
   static const uint8_t g_riscv_opcode_c[] = {0x02, 0x90};           // c.ebreak
+  static const uint8_t g_loongarch_opcode[] = {0x05, 0x00, 0x2a, 0x00}; // break
 
   switch (GetArchitecture().GetMachine()) {
   case llvm::Triple::aarch64:
@@ -541,6 +542,10 @@
                           : llvm::makeArrayRef(g_riscv_opcode);
   }
 
+  case llvm::Triple::loongarch32:
+  case llvm::Triple::loongarch64:
+    return llvm::makeArrayRef(g_loongarch_opcode);
+
   default:
     return llvm::createStringError(llvm::inconvertibleErrorCode(),
                                    "CPU type not supported!");
@@ -567,6 +572,8 @@
   case llvm::Triple::ppc64le:
   case llvm::Triple::riscv32:
   case llvm::Triple::riscv64:
+  case llvm::Triple::loongarch32:
+  case llvm::Triple::loongarch64:
     // On these architectures the PC doesn't get updated for breakpoint hits.
     return 0;
 


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