[lldb][RISCV] function calls support in lldb expressions (#99336)

[lldb][RISCV] add jitted function calls to ABI
Function calls support in LLDB expressions for RISCV: 1 of 4

Augments corresponding functionality to RISCV ABI, which allows to jit
lldb expressions and thus make function calls inside them. Only function
calls with integer and void function arguments and return value are
supported.

[lldb][RISCV] add JIT relocations resolver
Function calls support in LLDB expressions for RISCV: 2 of 4

Adds required RISCV relocations resolving functionality in lldb
ExecutionEngine.

[lldb][RISCV] RISC-V large code model in lldb expressions
Function calls support in LLDB expressions for RISCV: 3 of 4

This patch sets large code model in MCJIT settings for RISC-V 64-bit targets
that allows to make assembly jumps at any 64bit address. This is needed,
because resulted jitted code may contain more that +-2GB jumps, that are
not available in RISC-V with medium code model.

[lldb][RISCV] doubles support in lldb expressions
Function calls support in LLDB expressions for RISCV: 4 of 4

This patch adds desired feature flags in MCJIT compiler to enable
hard-float instructions if target supports them and allows to use floats
and doubles in lldb expressions.

1 files changed, 6 insertions, 0 deletions

diff --git a/lldb/source/Expression/IRExecutionUnit.cpp b/lldb/source/Expression/IRExecutionUnit.cpp
index 15ca2ddbbae0..baf70cbccc8c 100644
--- a/lldb/source/Expression/IRExecutionUnit.cpp
+++ b/lldb/source/Expression/IRExecutionUnit.cpp
@@ -277,6 +277,12 @@ void IRExecutionUnit::GetRunnableInfo(Status &error, lldb::addr_t &func_addr,
       .setMCJITMemoryManager(std::make_unique<MemoryManager>(*this))
       .setOptLevel(llvm::CodeGenOptLevel::Less);
 
+  // Resulted jitted code can be placed too far from the code in the binary
+  // and thus can contain more than +-2GB jumps, that are not available
+  // in RISC-V without large code model.
+  if (triple.isRISCV64())
+    builder.setCodeModel(llvm::CodeModel::Large);
+
   llvm::StringRef mArch;
   llvm::StringRef mCPU;
   llvm::SmallVector<std::string, 0> mAttrs;