Use feature flag for shadow frames

Summary: We have one-off ifdef's in a couple of spots to do a version check and then enable the feature. This moves it to a unified top-level definition that's only enabled for 3.10.

Reviewed By: martindemello

Differential Revision: D77456968

fbshipit-source-id: 8c23edfbf14fd5eed9024ccf5527144cf6508e6e

Author: DinoV

Jit/codegen/frame_asm.cpp

@@ -21,14 +21,9 @@
 using namespace asmjit;
 using namespace jit::hir;
 
-// Use a special define to keep it clear why much code changes in 3.12+
-#if PY_VERSION_HEX < 0x030C0000
-#define SHADOW_FRAMES 1
-#endif
-
 namespace jit::codegen {
 
-#ifdef SHADOW_FRAMES
+#ifdef ENABLE_SHADOW_FRAMES
 
 namespace shadow_frame {
 // Shadow stack frames appear at the beginning of native frames for jitted
@@ -48,7 +43,7 @@ constexpr x86::Mem getStackTopPtr(x86::Gp tstate_reg) {
 
 } // namespace shadow_frame
 
-#endif // SHADOW_FRAMES
+#endif // ENABLE_SHADOW_FRAMES
 
 #if PY_VERSION_HEX >= 0x030C0000
 
@@ -382,7 +377,7 @@ void FrameAsm::generateLinkFrame(
 void FrameAsm::generateUnlinkFrame(
     const x86::Gp& tstate_r,
     [[maybe_unused]] bool is_generator) {
-#ifdef SHADOW_FRAMES
+#ifdef ENABLE_SHADOW_FRAMES
   // It's safe to use caller saved registers in this function
   auto scratch_reg = tstate_r == x86::rsi ? x86::rdx : x86::rsi;
   x86::Mem shadow_stack_top_ptr = shadow_frame::getStackTopPtr(tstate_r);
@@ -435,13 +430,13 @@ void FrameAsm::generateUnlinkFrame(
     } else {
       as_->mov(x86::rax, saved_rax_ptr);
     }
-#ifdef SHADOW_FRAMES
+#ifdef ENABLE_SHADOW_FRAMES
     as_->bind(done);
   }
 #endif
 }
 
-#ifdef SHADOW_FRAMES
+#ifdef ENABLE_SHADOW_FRAMES
 void FrameAsm::linkOnStackShadowFrame(
     const x86::Gp& tstate_reg,
     const x86::Gp& scratch_reg) {
@@ -494,7 +489,7 @@ int FrameAsm::frameHeaderSize() {
     return 0;
   }
 
-#if defined(SHADOW_FRAMES)
+#if defined(ENABLE_SHADOW_FRAMES)
   return sizeof(FrameHeader);
 #elif defined(ENABLE_LIGHTWEIGHT_FRAMES)
   return sizeof(FrameHeader) + sizeof(PyObject*) * func_->code->co_framesize;

Jit/codegen/gen_asm.cpp

@@ -868,7 +868,7 @@ void NativeGenerator::generateFunctionEntry() {
 }
 
 void NativeGenerator::setupFrameAndSaveCallerRegisters(
-#ifdef SHADOW_FRAMES
+#ifdef ENABLE_SHADOW_FRAMES
     x86::Gp tstate_reg
 #endif
 ) {
@@ -913,7 +913,7 @@ void NativeGenerator::setupFrameAndSaveCallerRegisters(
   as_->sub(x86::rsp, spill_stack);
   env_.last_callee_saved_reg_off = spill_stack + saved_regs_size;
 
-#ifdef SHADOW_FRAMES
+#ifdef ENABLE_SHADOW_FRAMES
   frame_asm_.initializeFrameHeader(tstate_reg, x86::rax);
 #endif
 
@@ -1036,7 +1036,7 @@ void NativeGenerator::generatePrologue(
   as_->bind(native_entry_point);
 
   setupFrameAndSaveCallerRegisters(
-#ifdef SHADOW_FRAMES
+#ifdef ENABLE_SHADOW_FRAMES
       x86::r11
 #endif
   );
@@ -1372,7 +1372,7 @@ void NativeGenerator::generateResumeEntry() {
 
   generateFunctionEntry();
   setupFrameAndSaveCallerRegisters(
-#ifdef SHADOW_FRAMES
+#ifdef ENABLE_SHADOW_FRAMES
       x86::rcx
 #endif
   );

Jit/codegen/gen_asm.h

@@ -25,11 +25,6 @@
 #include <unordered_set>
 #include <vector>
 
-// Use a special define to keep it clear why much code changes in 3.12+
-#if PY_VERSION_HEX < 0x030C0000
-#define SHADOW_FRAMES 1
-#endif
-
 namespace jit::codegen {
 
 class NativeGenerator {
@@ -109,7 +104,7 @@ class NativeGenerator {
   void generateCode(asmjit::CodeHolder& code);
   void generateFunctionEntry();
   void setupFrameAndSaveCallerRegisters(
-#ifdef SHADOW_FRAMES
+#ifdef ENABLE_SHADOW_FRAMES
       asmjit::x86::Gp tstate_reg
 #endif
   );