Merge pull request #4269 from bylaws/jumpext

JIT: Avoid OOB EC bitmap checks in ExitFunction
FEX-Emu · Jan 14, 2025 · 8c02bd4 · 8c02bd4
2 parents f635a12 + c852a58
commit 8c02bd4
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Showing 2 changed files with 3 additions and 1 deletion.
diff --git a/FEXCore/Source/Interface/Core/ArchHelpers/Arm64Emitter.h b/FEXCore/Source/Interface/Core/ArchHelpers/Arm64Emitter.h
@@ -74,6 +74,8 @@ constexpr size_t PEB_EC_CODE_BITMAP_OFFSET = 0x368;
 constexpr size_t CPU_AREA_IN_SYSCALL_CALLBACK_OFFSET = 0x1;
 constexpr size_t CPU_AREA_EMULATOR_STACK_BASE_OFFSET = 0x8;
 constexpr size_t CPU_AREA_EMULATOR_DATA_OFFSET = 0x30;
+
+constexpr uint64_t EC_CODE_BITMAP_MAX_ADDRESS = 1ULL << 47;
 #endif
 
 // Will force one single instruction block to be generated first if set when entering the JIT filling SRA.

diff --git a/FEXCore/Source/Interface/Core/JIT/BranchOps.cpp b/FEXCore/Source/Interface/Core/JIT/BranchOps.cpp
@@ -53,7 +53,7 @@ DEF_OP(ExitFunction) {
 
   if (IsInlineConstant(Op->NewRIP, &NewRIP) || IsInlineEntrypointOffset(Op->NewRIP, &NewRIP)) {
 #ifdef _M_ARM_64EC
-    if (RtlIsEcCode(NewRIP)) {
+    if (NewRIP < EC_CODE_BITMAP_MAX_ADDRESS && RtlIsEcCode(NewRIP)) {
       add(ARMEmitter::Size::i64Bit, ARMEmitter::Reg::rsp, StaticRegisters[X86State::REG_RSP], 0);
       LoadConstant(ARMEmitter::Size::i64Bit, EC_CALL_CHECKER_PC_REG, NewRIP);
       ldr(TMP2, STATE_PTR(CpuStateFrame, Pointers.Common.ExitFunctionEC));