[ENCODEGEN,X64] Support negative offset for LEA32rm

Author: aengelke

tpde-encodegen/src/x64/EncCompilerTemplate.hpp

@@ -58,7 +58,7 @@ struct EncodeCompiler {
 
     [[nodiscard]] static std::optional<i32> encodeable_as_imm32_sext(GenericValuePart &gv) noexcept;
     [[nodiscard]] static std::optional<FeMem> encodeable_as_mem(GenericValuePart &gv, unsigned align) noexcept;
-    [[nodiscard]] static std::optional<FeMem> encodeable_with(GenericValuePart &gv, FeMem other) noexcept;
+    [[nodiscard]] static std::optional<FeMem> encodeable_with(GenericValuePart &gv, FeMem other, bool addr32 = false) noexcept;
     void          try_salvage_or_materialize(GenericValuePart &gv,
                                              ScratchReg     &dst_scratch,
                                              u8              bank,
@@ -176,10 +176,10 @@ template <typename Adaptor,
           class BaseTy,
           typename Config>
 std::optional<FeMem> EncodeCompiler<Adaptor, Derived, BaseTy, Config>::
-    encodeable_with(GenericValuePart &gv, FeMem other) noexcept {
-    const auto disp_encodeable = [](u64 a, u64 b) -> std::optional<i32> {
+    encodeable_with(GenericValuePart &gv, FeMem other, bool addr32) noexcept {
+    const auto disp_encodeable = [addr32](u64 a, u64 b) -> std::optional<i32> {
         auto sum = static_cast<i32>(a + b);
-        if (static_cast<i64>(sum) == static_cast<i64>(a + b))
+        if (addr32 || static_cast<i64>(sum) == static_cast<i64>(a + b))
             return sum;
         return std::nullopt;
     };

tpde-encodegen/src/x64/Target.cpp

@@ -229,7 +229,8 @@ void EncodingTargetX64::get_inst_candidates(
       unsigned sc = has_idx ? mi.getOperand(memop_start + 1).getImm() : 0;
       std::string_view idx = has_idx ? "FE_AX" : "FE_NOREG";
       auto off = mi.getOperand(memop_start + 3).getImm();
-      auto cond = std::format("FE_MEM(FE_NOREG, {}, {}, {})", sc, idx, off);
+      auto cond = std::format(
+          "FE_MEM(FE_NOREG, {}, {}, {}), {}", sc, idx, off, mnem == "LEA32rm");
 
       candidates.emplace_back(
           memop_start,
@@ -275,7 +276,8 @@ void EncodingTargetX64::get_inst_candidates(
         mi.getOperand(memop_start + 1).getImm() == 1 &&
         mi.getOperand(memop_start + 3).isImm()) {
       auto off = mi.getOperand(memop_start + 3).getImm();
-      auto cond = std::format("FE_MEM(FE_AX, 0, FE_NOREG, {})", off);
+      auto cond = std::format(
+          "FE_MEM(FE_AX, 0, FE_NOREG, {}), {}", off, mnem == "LEA32rm");
 
       candidates.emplace_back(
           memop_start + 2,

tpde-llvm/test/filetest/add.ll

@@ -267,8 +267,7 @@ define void @add_i32_invert(i32 %0) {
 ; X64-NEXT:    mov rbp, rsp
 ; X64-NEXT:    nop word ptr [rax + rax]
 ; X64-NEXT:    sub rsp, 0x30
-; X64-NEXT:    mov eax, 0xffffffff
-; X64-NEXT:    lea edi, [rdi + rax]
+; X64-NEXT:    lea edi, [rdi - 0x1]
 ; X64-NEXT:    add rsp, 0x30
 ; X64-NEXT:    pop rbp
 ; X64-NEXT:    ret
@@ -345,8 +344,7 @@ define void @add_i32_FFFFFFFF(i32 %0) {
 ; X64-NEXT:    mov rbp, rsp
 ; X64-NEXT:    nop word ptr [rax + rax]
 ; X64-NEXT:    sub rsp, 0x30
-; X64-NEXT:    mov eax, 0xffffffff
-; X64-NEXT:    lea edi, [rdi + rax]
+; X64-NEXT:    lea edi, [rdi - 0x1]
 ; X64-NEXT:    add rsp, 0x30
 ; X64-NEXT:    pop rbp
 ; X64-NEXT:    ret