Change CORJIT_FLAG_READYTORUN and CORJIT_FLAG_PREJIT to CORJIT_FLAG_AOT (#113850)

CORJIT_FLAG_READYTORUN and CORJIT_FLAG_PREJIT were always both set
together. Introduce a new name to be more explicit of a concept
that includes both ReadyToRun and NativeAOT (AOT == Ahead Of Time).

Introduce new JIT helpers `IsAot` (for either NativeAOT or R2R),
`IsNativeAot`, and `IsReadyToRun`.

Remove the name "ngen" in a bunch of places in the JIT code.

Author: BruceForstall

src/coreclr/inc/corjitflags.h

@@ -40,10 +40,10 @@ class CORJIT_FLAGS
         CORJIT_FLAG_ALT_JIT                 = 8, // JIT should consider itself an ALT_JIT
         CORJIT_FLAG_FROZEN_ALLOC_ALLOWED    = 9, // JIT is allowed to use *_MAYBEFROZEN allocators
         // CORJIT_FLAG_UNUSED               = 10,
-        CORJIT_FLAG_READYTORUN              = 11, // Use version-resilient code generation
+        CORJIT_FLAG_AOT                     = 11, // Do ahead-of-time code generation (ReadyToRun or NativeAOT)
         CORJIT_FLAG_PROF_ENTERLEAVE         = 12, // Instrument prologues/epilogues
         CORJIT_FLAG_PROF_NO_PINVOKE_INLINE  = 13, // Disables PInvoke inlining
-        CORJIT_FLAG_PREJIT                  = 14, // prejit is the execution engine.
+        // CORJIT_FLAG_UNUSED               = 14,
         CORJIT_FLAG_RELOC                   = 15, // Generate relocatable code
         CORJIT_FLAG_IL_STUB                 = 16, // method is an IL stub
         CORJIT_FLAG_PROCSPLIT               = 17, // JIT should separate code into hot and cold sections

src/coreclr/inc/jiteeversionguid.h

@@ -37,11 +37,11 @@
 
 #include <minipal/guid.h>
 
-constexpr GUID JITEEVersionIdentifier = { /* 27f02512-bc1c-44b7-8d96-cf1a3beadfbe */
-    0x27f02512,
-    0xbc1c,
-    0x44b7,
-    {0x8d, 0x96, 0xcf, 0x1a, 0x3b, 0xea, 0xdf, 0xbe}
+constexpr GUID JITEEVersionIdentifier = { /* 7139df75-63b2-4610-9a53-f9a86f474db8 */
+    0x7139df75,
+    0x63b2,
+    0x4610,
+    {0x9a, 0x53, 0xf9, 0xa8, 0x6f, 0x47, 0x4d, 0xb8}
   };
 
 #endif // JIT_EE_VERSIONING_GUID_H

src/coreclr/jit/assertionprop.cpp

@@ -883,7 +883,7 @@ void Compiler::optPrintAssertion(AssertionDsc* curAssertion, AssertionIndex asse
                 if (curAssertion->op1.kind == O1K_EXACT_TYPE)
                 {
                     ssize_t iconVal = curAssertion->op2.u1.iconVal;
-                    if (IsTargetAbi(CORINFO_NATIVEAOT_ABI) || opts.IsReadyToRun())
+                    if (IsAot())
                     {
                         printf("Exact Type MT(0x%p)", dspPtr(iconVal));
                     }
@@ -903,7 +903,7 @@ void Compiler::optPrintAssertion(AssertionDsc* curAssertion, AssertionIndex asse
                 else if (curAssertion->op1.kind == O1K_SUBTYPE)
                 {
                     ssize_t iconVal = curAssertion->op2.u1.iconVal;
-                    if (IsTargetAbi(CORINFO_NATIVEAOT_ABI) || opts.IsReadyToRun())
+                    if (IsAot())
                     {
                         printf("MT(0x%p)", dspPtr(iconVal));
                     }

src/coreclr/jit/codegenarmarch.cpp

@@ -630,7 +630,7 @@ void CodeGen::genEmitGSCookieCheck(bool pushReg)
     }
     else
     {
-        // Ngen case - GS cookie constant needs to be accessed through an indirection.
+        // AOT case - GS cookie constant needs to be accessed through an indirection.
         instGen_Set_Reg_To_Imm(EA_HANDLE_CNS_RELOC, regGSConst, (ssize_t)compiler->gsGlobalSecurityCookieAddr,
                                INS_FLAGS_DONT_CARE DEBUGARG((size_t)THT_GSCookieCheck) DEBUGARG(GTF_EMPTY));
         GetEmitter()->emitIns_R_R_I(INS_ldr, EA_PTRSIZE, regGSConst, regGSConst, 0);
@@ -4622,7 +4622,7 @@ void CodeGen::genPushCalleeSavedRegisters()
     // - Generate fully interruptible code for loops that contains calls
     // - Generate fully interruptible code for leaf methods
     //
-    // Given the limited benefit from this optimization (<10k for CoreLib NGen image), the extra complexity
+    // Given the limited benefit from this optimization (<10k for CoreLib AOT image), the extra complexity
     // is not worth it.
     //
     rsPushRegs |= RBM_LR; // We must save the return address (in the LR register)

src/coreclr/jit/codegencommon.cpp

@@ -1768,9 +1768,9 @@ void CodeGen::genGenerateCode(void** codePtr, uint32_t* nativeSizeOfCode)
     DoPhase(this, PHASE_EMIT_GCEH, &CodeGen::genEmitUnwindDebugGCandEH);
 
 #ifdef DEBUG
-    // For R2R/NAOT not all these helpers are implemented. So don't ask for them.
+    // For AOT not all these helpers are implemented. So don't ask for them.
     //
-    if (genWriteBarrierUsed && JitConfig.EnableExtraSuperPmiQueries() && !compiler->opts.IsReadyToRun())
+    if (genWriteBarrierUsed && JitConfig.EnableExtraSuperPmiQueries() && !compiler->IsAot())
     {
         void* ignored;
         for (int i = CORINFO_HELP_ASSIGN_REF; i <= CORINFO_HELP_BULK_WRITEBARRIER; i++)
@@ -1944,13 +1944,16 @@ void CodeGen::genGenerateMachineCode()
 
         printf("; %s code\n", compiler->compGetTieringName(false));
 
-        if (compiler->IsTargetAbi(CORINFO_NATIVEAOT_ABI))
+        if (compiler->IsAot())
         {
-            printf("; NativeAOT compilation\n");
-        }
-        else if (compiler->opts.jitFlags->IsSet(JitFlags::JIT_FLAG_READYTORUN))
-        {
-            printf("; ReadyToRun compilation\n");
+            if (compiler->IsTargetAbi(CORINFO_NATIVEAOT_ABI))
+            {
+                printf("; NativeAOT compilation\n");
+            }
+            else
+            {
+                printf("; ReadyToRun compilation\n");
+            }
         }
 
         if (compiler->opts.IsOSR())
@@ -2031,8 +2034,7 @@ void CodeGen::genGenerateMachineCode()
     GetEmitter()->emitBegFN(isFramePointerUsed()
 #if defined(DEBUG)
                                 ,
-                            (compiler->compCodeOpt() != Compiler::SMALL_CODE) &&
-                                !compiler->opts.jitFlags->IsSet(JitFlags::JIT_FLAG_PREJIT)
+                            (compiler->compCodeOpt() != Compiler::SMALL_CODE) && !compiler->IsAot()
 #endif
     );
 

src/coreclr/jit/codegenloongarch64.cpp

@@ -4664,7 +4664,7 @@ void CodeGen::genEmitGSCookieCheck(bool pushReg)
     }
     else
     {
-        //// Ngen case - GS cookie constant needs to be accessed through an indirection.
+        // AOT case - GS cookie constant needs to be accessed through an indirection.
         // instGen_Set_Reg_To_Imm(EA_HANDLE_CNS_RELOC, regGSConst, (ssize_t)compiler->gsGlobalSecurityCookieAddr);
         // GetEmitter()->emitIns_R_R_I(INS_ld_d, EA_PTRSIZE, regGSConst, regGSConst, 0);
         if (compiler->opts.compReloc)
@@ -7108,7 +7108,7 @@ void CodeGen::genPushCalleeSavedRegisters(regNumber initReg, bool* pInitRegZeroe
     // - Generate fully interruptible code for loops that contains calls
     // - Generate fully interruptible code for leaf methods
     //
-    // Given the limited benefit from this optimization (<10k for SPCL NGen image), the extra complexity
+    // Given the limited benefit from this optimization (<10k for SPCL AOT image), the extra complexity
     // is not worth it.
     //
 

src/coreclr/jit/codegenriscv64.cpp

@@ -4669,7 +4669,7 @@ void CodeGen::genEmitGSCookieCheck(bool pushReg)
     }
     else
     {
-        //// Ngen case - GS cookie constant needs to be accessed through an indirection.
+        // AOT case - GS cookie constant needs to be accessed through an indirection.
         // instGen_Set_Reg_To_Imm(EA_HANDLE_CNS_RELOC, regGSConst, (ssize_t)compiler->gsGlobalSecurityCookieAddr);
         // GetEmitter()->emitIns_R_R_I(INS_ld_d, EA_PTRSIZE, regGSConst, regGSConst, 0);
         if (compiler->opts.compReloc)
@@ -6914,7 +6914,7 @@ void CodeGen::genPushCalleeSavedRegisters(regNumber initReg, bool* pInitRegZeroe
     // - Generate fully interruptible code for loops that contains calls
     // - Generate fully interruptible code for leaf methods
     //
-    // Given the limited benefit from this optimization (<10k for SPCL NGen image), the extra complexity
+    // Given the limited benefit from this optimization (<10k for SPCL AOT image), the extra complexity
     // is not worth it.
     //
 

src/coreclr/jit/codegenxarch.cpp

@@ -156,7 +156,7 @@ void CodeGen::genEmitGSCookieCheck(bool pushReg)
     }
     else
     {
-        // Ngen case - GS cookie value needs to be accessed through an indirection.
+        // AOT case - GS cookie value needs to be accessed through an indirection.
 
         pushedRegs = genPushRegs(regMaskGSCheck, &byrefPushedRegs, &norefPushedRegs);
 
@@ -9821,7 +9821,7 @@ void CodeGen::genProfilingEnterCallback(regNumber initReg, bool* pInitRegZeroed)
     // RCX = ProfilerMethHnd
     if (compiler->compProfilerMethHndIndirected)
     {
-        // Profiler hooks enabled during Ngen time.
+        // Profiler hooks enabled during AOT.
         // Profiler handle needs to be accessed through an indirection of a pointer.
         GetEmitter()->emitIns_R_AI(INS_mov, EA_PTR_DSP_RELOC, REG_ARG_0, (ssize_t)compiler->compProfilerMethHnd);
     }
@@ -9900,7 +9900,7 @@ void CodeGen::genProfilingEnterCallback(regNumber initReg, bool* pInitRegZeroed)
     // R14 = ProfilerMethHnd
     if (compiler->compProfilerMethHndIndirected)
     {
-        // Profiler hooks enabled during Ngen time.
+        // Profiler hooks enabled during AOT.
         // Profiler handle needs to be accessed through an indirection of a pointer.
         GetEmitter()->emitIns_R_AI(INS_mov, EA_PTR_DSP_RELOC, REG_PROFILER_ENTER_ARG_0,
                                    (ssize_t)compiler->compProfilerMethHnd);
@@ -9982,7 +9982,7 @@ void CodeGen::genProfilingLeaveCallback(unsigned helper)
     // RCX = ProfilerMethHnd
     if (compiler->compProfilerMethHndIndirected)
     {
-        // Profiler hooks enabled during Ngen time.
+        // Profiler hooks enabled during AOT.
         // Profiler handle needs to be accessed through an indirection of an address.
         GetEmitter()->emitIns_R_AI(INS_mov, EA_PTR_DSP_RELOC, REG_ARG_0, (ssize_t)compiler->compProfilerMethHnd);
     }
@@ -11718,7 +11718,7 @@ bool CodeGenInterface::genCodeIndirAddrCanBeEncodedAsZeroRelOffset(size_t addr)
 //
 bool CodeGenInterface::genCodeIndirAddrNeedsReloc(size_t addr)
 {
-    // If generating relocatable ngen code, then all code addr should go through relocation
+    // If generating relocatable AOT code, then all code addr should go through relocation
     if (compiler->opts.compReloc)
     {
         return true;
@@ -11751,7 +11751,7 @@ bool CodeGenInterface::genCodeIndirAddrNeedsReloc(size_t addr)
 //
 bool CodeGenInterface::genCodeAddrNeedsReloc(size_t addr)
 {
-    // If generating relocatable ngen code, then all code addr should go through relocation
+    // If generating relocatable AOT code, then all code addr should go through relocation
     if (compiler->opts.compReloc)
     {
         return true;

src/coreclr/jit/compiler.cpp

@@ -2297,7 +2297,7 @@ void Compiler::compInitOptions(JitFlags* jitFlags)
 #ifdef DEBUG
 
     const JitConfigValues::MethodSet* pfAltJit;
-    if (jitFlags->IsSet(JitFlags::JIT_FLAG_PREJIT))
+    if (jitFlags->IsSet(JitFlags::JIT_FLAG_AOT))
     {
         pfAltJit = &JitConfig.AltJitNgen();
     }
@@ -2323,7 +2323,7 @@ void Compiler::compInitOptions(JitFlags* jitFlags)
 #else // !DEBUG
 
     const char* altJitVal;
-    if (jitFlags->IsSet(JitFlags::JIT_FLAG_PREJIT))
+    if (jitFlags->IsSet(JitFlags::JIT_FLAG_AOT))
     {
         altJitVal = JitConfig.AltJitNgen().list();
     }
@@ -2927,13 +2927,13 @@ void Compiler::compInitOptions(JitFlags* jitFlags)
     // Honour DOTNET_JitELTHookEnabled or STRESS_PROFILER_CALLBACKS stress mode
     // only if VM has not asked us to generate profiler hooks in the first place.
     // That is, override VM only if it hasn't asked for a profiler callback for this method.
-    // Don't run this stress mode when pre-JITing, as we would need to emit a relocation
+    // Don't run this stress mode under AOT, as we would need to emit a relocation
     // for the call to the fake ELT hook, which wouldn't make sense, as we can't store that
-    // in the pre-JIT image.
+    // in the AOT image.
     if (!compProfilerHookNeeded)
     {
         if ((JitConfig.JitELTHookEnabled() != 0) ||
-            (!jitFlags->IsSet(JitFlags::JIT_FLAG_PREJIT) && compStressCompile(STRESS_PROFILER_CALLBACKS, 5)))
+            (!jitFlags->IsSet(JitFlags::JIT_FLAG_AOT) && compStressCompile(STRESS_PROFILER_CALLBACKS, 5)))
         {
             opts.compJitELTHookEnabled = true;
         }
@@ -3049,7 +3049,7 @@ void Compiler::compInitOptions(JitFlags* jitFlags)
 
     if (opts.compProcedureSplitting)
     {
-        // Note that opts.compdbgCode is true under ngen for checked assemblies!
+        // Note that opts.compDbgCode is true under AOT for checked assemblies!
         opts.compProcedureSplitting = !opts.compDbgCode || enableFakeSplitting;
 
 #ifdef DEBUG
@@ -3155,9 +3155,9 @@ void Compiler::compInitOptions(JitFlags* jitFlags)
             printf("OPTIONS: optimizer should use profile data\n");
         }
 
-        if (jitFlags->IsSet(JitFlags::JIT_FLAG_PREJIT))
+        if (jitFlags->IsSet(JitFlags::JIT_FLAG_AOT))
         {
-            printf("OPTIONS: Jit invoked for ngen\n");
+            printf("OPTIONS: Jit invoked for AOT\n");
         }
     }
 #endif
@@ -3234,15 +3234,15 @@ void Compiler::compInitOptions(JitFlags* jitFlags)
 
 bool Compiler::compJitHaltMethod()
 {
-    /* This method returns true when we use an INS_BREAKPOINT to allow us to step into the generated native code */
-    /* Note that this these two "Jit" environment variables also work for ngen images */
+    // This method returns true when we use an INS_BREAKPOINT to allow us to step into the generated native code.
+    // Note that these two "Jit" environment variables also work for AOT images.
 
     if (JitConfig.JitHalt().contains(info.compMethodHnd, info.compClassHnd, &info.compMethodInfo->args))
     {
         return true;
     }
 
-    /* Use this Hash variant when there are a lot of method with the same name and different signatures */
+    // Use this Hash variant when there are a lot of method with the same name and different signatures.
 
     unsigned fJitHashHaltVal = (unsigned)JitConfig.JitHashHalt();
     if ((fJitHashHaltVal != (unsigned)-1) && (fJitHashHaltVal == info.compMethodHash()))
@@ -3721,9 +3721,8 @@ void Compiler::compSetOptimizationLevel()
     {
         theMinOptsValue = true;
     }
-    // For PREJIT we never drop down to MinOpts
-    // unless unless CLFLG_MINOPT is set
-    else if (!opts.jitFlags->IsSet(JitFlags::JIT_FLAG_PREJIT))
+    // For AOT we never drop down to MinOpts unless unless CLFLG_MINOPT is set
+    else if (!IsAot())
     {
         if ((unsigned)JitConfig.JitMinOptsCodeSize() < info.compILCodeSize)
         {
@@ -3763,10 +3762,9 @@ void Compiler::compSetOptimizationLevel()
         }
     }
 #else  // !DEBUG
-    // Retail check if we should force Minopts due to the complexity of the method
-    // For PREJIT we never drop down to MinOpts
-    // unless unless CLFLG_MINOPT is set
-    if (!theMinOptsValue && !opts.jitFlags->IsSet(JitFlags::JIT_FLAG_PREJIT) &&
+    // Retail check if we should force Minopts due to the complexity of the method.
+    // For AOT we never drop down to MinOpts unless unless CLFLG_MINOPT is set.
+    if (!theMinOptsValue && !IsAot() &&
         ((DEFAULT_MIN_OPTS_CODE_SIZE < info.compILCodeSize) || (DEFAULT_MIN_OPTS_INSTR_COUNT < opts.instrCount) ||
          (DEFAULT_MIN_OPTS_BB_COUNT < fgBBcount) || (DEFAULT_MIN_OPTS_LV_NUM_COUNT < lvaCount) ||
          (DEFAULT_MIN_OPTS_LV_REF_COUNT < opts.lvRefCount)))
@@ -3835,14 +3833,13 @@ void Compiler::compSetOptimizationLevel()
             codeGen->setFrameRequired(true);
 #endif
 
-        if (opts.OptimizationDisabled() ||
-            (opts.jitFlags->IsSet(JitFlags::JIT_FLAG_PREJIT) && !IsTargetAbi(CORINFO_NATIVEAOT_ABI)))
+        if (opts.OptimizationDisabled() || IsReadyToRun())
         {
-            // The JIT doesn't currently support loop alignment for prejitted images outside NativeAOT.
+            // The JIT doesn't currently support loop alignment for AOT images outside NativeAOT.
             // (The JIT doesn't know the final address of the code, hence
             // it can't align code based on unknown addresses.)
 
-            codeGen->SetAlignLoops(false); // loop alignment not supported for prejitted code
+            codeGen->SetAlignLoops(false); // loop alignment not supported for AOT code
         }
         else
         {
@@ -6677,11 +6674,11 @@ void Compiler::compCompileFinish()
     }
 #endif // TRACK_ENREG_STATS
 
-    // Only call _DbgBreakCheck when we are jitting, not when we are ngen-ing
-    // For ngen the int3 or breakpoint instruction will be right at the
-    // start of the ngen method and we will stop when we execute it.
+    // Only call _DbgBreakCheck when we are jitting, not when we are generating AOT code.
+    // For AOT the int3 or breakpoint instruction will be right at the
+    // start of the AOT method and we will stop when we execute it.
     //
-    if (!opts.jitFlags->IsSet(JitFlags::JIT_FLAG_PREJIT))
+    if (!IsAot())
     {
         if (compJitHaltMethod())
         {
@@ -6948,9 +6945,9 @@ int Compiler::compCompileHelper(CORINFO_MODULE_HANDLE classPtr,
 
     const bool forceInline = !!(info.compFlags & CORINFO_FLG_FORCEINLINE);
 
-    if (!compIsForInlining() && opts.jitFlags->IsSet(JitFlags::JIT_FLAG_PREJIT))
+    if (!compIsForInlining() && IsAot())
     {
-        // We're prejitting the root method. We also will analyze it as
+        // We're AOT compiling the root method. We also will analyze it as
         // a potential inline candidate.
         InlineResult prejitResult(this, info.compMethodHnd, "prejit");