[lldb] Add a test for lea_rsp_pattern_p to x86 unwinder (NFC)

[xgupta]

This commit adds a test for lea_rsp_pattern_p which was previously due as FIXME.

[llvmbot]

@llvm/pr-subscribers-lldb

Author: Shivam Gupta (xgupta)

Changes

This commit adds a test for lea_rsp_pattern_p which was previously due as FIXME.

---

Full diff: https://github.com/llvm/llvm-project/pull/94852.diff

1 Files Affected:

• (modified) lldb/unittests/UnwindAssembly/x86/Testx86AssemblyInspectionEngine.cpp (+23-1)

diff --git a/lldb/unittests/UnwindAssembly/x86/Testx86AssemblyInspectionEngine.cpp b/lldb/unittests/UnwindAssembly/x86/Testx86AssemblyInspectionEngine.cpp
index 277cc14ce50c9..597e5b2e40d5e 100644
--- a/lldb/unittests/UnwindAssembly/x86/Testx86AssemblyInspectionEngine.cpp
+++ b/lldb/unittests/UnwindAssembly/x86/Testx86AssemblyInspectionEngine.cpp
@@ -1731,7 +1731,29 @@ TEST_F(Testx86AssemblyInspectionEngine, TestAddESP) {
   EXPECT_EQ(4 - 16, row_sp->GetCFAValue().GetOffset());
 }
 
-// FIXME add test for lea_rsp_pattern_p
+TEST_F(Testx86AssemblyInspectionEngine, TestLEA_RSP_Pattern) {
+  UnwindPlan::Row::RegisterLocation regloc;
+  UnwindPlan::RowSP row_sp;
+  AddressRange sample_range;
+  UnwindPlan unwind_plan(eRegisterKindLLDB);
+  std::unique_ptr<x86AssemblyInspectionEngine> engine = Getx86_64Inspector();
+
+  uint8_t data[] = {
+      0x8d, 0x64, 0x24, 0x10, // lea rsp, [rsp + 0x10]
+      0x90                    // nop
+  };
+
+  sample_range = AddressRange(0x1000, sizeof(data));
+
+  EXPECT_TRUE(engine->GetNonCallSiteUnwindPlanFromAssembly(
+      data, sizeof(data), sample_range, unwind_plan));
+
+  row_sp = unwind_plan.GetRowForFunctionOffset(0);
+  EXPECT_EQ(0ull, row_sp->GetOffset());
+  EXPECT_TRUE(row_sp->GetCFAValue().GetRegisterNumber() == k_rsp);
+  EXPECT_TRUE(row_sp->GetCFAValue().IsRegisterPlusOffset() == true);
+  EXPECT_EQ(8, row_sp->GetCFAValue().GetOffset());
+}
 
 TEST_F(Testx86AssemblyInspectionEngine, TestPopRBX) {
   UnwindPlan::Row::RegisterLocation regloc;

[jasonmolenda]

Hi, thanks for the PR. I wrote the x86 unwinder but I don't work with the ISA very often any more, I'm a little confused. Shouldn't the sp offset after this instruction executes be 16? The test is testing for 8. I'm sure I've misunderstood the effects of the instruction.

[jasonmolenda]

Ah wait, it's because x86_64 functions on entry have the CFA == $rsp+8, right. So you add 16 to rsp and now the CFA is $rsp-8. This is good to merge. Do you have access to do that yourself?

[xgupta]

Thanks @jasonmolenda for the review. I do have commit access to merge it.