[lldb][RISCV] function prologue backtrace fix

[dlav-sc]

CreateFunctionEntryUnwindPlan RISCV ABI function fix needed to receive a valid backtrace at the start of functions.

Fixed tests for RISCV target:

TestNumThreads.NumberOfThreadsTestCase
TestCPPExceptionBreakpoints.CPPBreakpointTestCase
TestStepThroughTrampoline.StepThroughTrampoline
TestOSPluginStepping.TestOSPluginStepping
TestSteppingOutWithArtificialFrames.TestArtificialFrameThreadStepOut1 TestStepAvoidsRegexp.StepAvoidsRegexTestCase
TestInlineStepping.TestInlineStepping
TestStepOverBreakpoint.StepOverBreakpointsTestCase TestStepOverBreakpoint.StepOverBreakpointsTestCase TestSteppingOutWithArtificialFrames.TestArtificialFrameThreadStepOut1 TestTailCallFrameSBAPI.TestTailCallFrameSBAPI
TestThreadPlanUserBreakpoint.ThreadPlanUserBreakpointsTestCase

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[llvmbot]

@llvm/pr-subscribers-lldb

Author: None (dlav-sc)

Changes

CreateFunctionEntryUnwindPlan RISCV ABI function fix needed to receive a valid backtrace at the start of functions.

Fixed tests for RISCV target:

TestNumThreads.NumberOfThreadsTestCase
TestCPPExceptionBreakpoints.CPPBreakpointTestCase
TestStepThroughTrampoline.StepThroughTrampoline
TestOSPluginStepping.TestOSPluginStepping
TestSteppingOutWithArtificialFrames.TestArtificialFrameThreadStepOut1 TestStepAvoidsRegexp.StepAvoidsRegexTestCase
TestInlineStepping.TestInlineStepping
TestStepOverBreakpoint.StepOverBreakpointsTestCase TestStepOverBreakpoint.StepOverBreakpointsTestCase TestSteppingOutWithArtificialFrames.TestArtificialFrameThreadStepOut1 TestTailCallFrameSBAPI.TestTailCallFrameSBAPI
TestThreadPlanUserBreakpoint.ThreadPlanUserBreakpointsTestCase

---

Full diff: https://github.com/llvm/llvm-project/pull/99043.diff

1 Files Affected:

• (modified) lldb/source/Plugins/ABI/RISCV/ABISysV_riscv.cpp (+4-3)

diff --git a/lldb/source/Plugins/ABI/RISCV/ABISysV_riscv.cpp b/lldb/source/Plugins/ABI/RISCV/ABISysV_riscv.cpp
index 6395f5bb5bd9b..35d4f0521bf1f 100644
--- a/lldb/source/Plugins/ABI/RISCV/ABISysV_riscv.cpp
+++ b/lldb/source/Plugins/ABI/RISCV/ABISysV_riscv.cpp
@@ -13,6 +13,7 @@
 
 #include "llvm/IR/DerivedTypes.h"
 
+#include "Utility/RISCV_DWARF_Registers.h"
 #include "lldb/Core/PluginManager.h"
 #include "lldb/Core/Value.h"
 #include "lldb/Core/ValueObjectConstResult.h"
@@ -643,9 +644,9 @@ bool ABISysV_riscv::CreateFunctionEntryUnwindPlan(UnwindPlan &unwind_plan) {
   unwind_plan.Clear();
   unwind_plan.SetRegisterKind(eRegisterKindDWARF);
 
-  uint32_t pc_reg_num = LLDB_REGNUM_GENERIC_PC;
-  uint32_t sp_reg_num = LLDB_REGNUM_GENERIC_SP;
-  uint32_t ra_reg_num = LLDB_REGNUM_GENERIC_RA;
+  uint32_t pc_reg_num = riscv_dwarf::dwarf_gpr_pc;
+  uint32_t sp_reg_num = riscv_dwarf::dwarf_gpr_sp;
+  uint32_t ra_reg_num = riscv_dwarf::dwarf_gpr_ra;
 
   UnwindPlan::RowSP row(new UnwindPlan::Row);
 

[DavidSpickett]

The other ABI plugins use the dwarf indexes and I guess that has to be the case because the unwind plan's type is dwarf. Adding @jasonmolenda just in case there's anything more to it.

[clayborg]

LGTM

[clayborg]

Since we specify here that we are using DWARF registers, then the change below is correct,

[jasonmolenda]

Agreed, this fix is correct, thanks for the PR. The register numbering in the UnwindPlan can be any eRegisterKind, but it does need to be self consistent, and this was not. Do you have permissions to merge this PR? I can do that for you if not.

[dlav-sc]

Agreed, this fix is correct, thanks for the PR. The register numbering in the UnwindPlan can be any eRegisterKind, but it does need to be self consistent, and this was not. Do you have permissions to merge this PR? I can do that for you if not.

Thanks for the review. I don't have permissions, please merge it yourself.

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