Decouple JIT_FLAG_PREJIT from HW intrinsics (#22117)

Per dotnet/corert#6836 (comment) moving the decision whether to enable HW intrinsics to the EE side.

1 files changed, 69 insertions, 72 deletions

diff --git a/src/jit/compiler.cpp b/src/jit/compiler.cpp
index 58197f9532..2c24df922c 100644
--- a/src/jit/compiler.cpp
+++ b/src/jit/compiler.cpp
@@ -2364,83 +2364,79 @@ void Compiler::compSetProcessor()
 #ifdef _TARGET_XARCH_
     opts.compSupportsISA = 0;
 
-    if (!jitFlags.IsSet(JitFlags::JIT_FLAG_PREJIT))
-    {
 #ifdef FEATURE_CORECLR
-        if (JitConfig.EnableHWIntrinsic())
+    if (JitConfig.EnableHWIntrinsic())
+    {
+        opts.setSupportedISA(InstructionSet_Base);
+
+        if (JitConfig.EnableSSE())
         {
-            opts.setSupportedISA(InstructionSet_Base);
+            opts.setSupportedISA(InstructionSet_SSE);
+#ifdef _TARGET_AMD64_
+            opts.setSupportedISA(InstructionSet_SSE_X64);
+#endif // _TARGET_AMD64_
 
-            if (JitConfig.EnableSSE())
+            if (JitConfig.EnableSSE2())
             {
-                opts.setSupportedISA(InstructionSet_SSE);
+                opts.setSupportedISA(InstructionSet_SSE2);
 #ifdef _TARGET_AMD64_
-                opts.setSupportedISA(InstructionSet_SSE_X64);
+                opts.setSupportedISA(InstructionSet_SSE2_X64);
 #endif // _TARGET_AMD64_
 
-                if (JitConfig.EnableSSE2())
+                if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_AES) && JitConfig.EnableAES())
                 {
-                    opts.setSupportedISA(InstructionSet_SSE2);
-#ifdef _TARGET_AMD64_
-                    opts.setSupportedISA(InstructionSet_SSE2_X64);
-#endif // _TARGET_AMD64_
+                    opts.setSupportedISA(InstructionSet_AES);
+                }
 
-                    if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_AES) && JitConfig.EnableAES())
-                    {
-                        opts.setSupportedISA(InstructionSet_AES);
-                    }
+                if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_PCLMULQDQ) && JitConfig.EnablePCLMULQDQ())
+                {
+                    opts.setSupportedISA(InstructionSet_PCLMULQDQ);
+                }
 
-                    if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_PCLMULQDQ) && JitConfig.EnablePCLMULQDQ())
-                    {
-                        opts.setSupportedISA(InstructionSet_PCLMULQDQ);
-                    }
+                // We need to additionaly check that COMPlus_EnableSSE3_4 is set, as that
+                // is a prexisting config flag that controls the SSE3+ ISAs
+                if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_SSE3) && JitConfig.EnableSSE3() && JitConfig.EnableSSE3_4())
+                {
+                    opts.setSupportedISA(InstructionSet_SSE3);
 
-                    // We need to additionaly check that COMPlus_EnableSSE3_4 is set, as that
-                    // is a prexisting config flag that controls the SSE3+ ISAs
-                    if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_SSE3) && JitConfig.EnableSSE3() &&
-                        JitConfig.EnableSSE3_4())
+                    if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_SSSE3) && JitConfig.EnableSSSE3())
                     {
-                        opts.setSupportedISA(InstructionSet_SSE3);
+                        opts.setSupportedISA(InstructionSet_SSSE3);
 
-                        if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_SSSE3) && JitConfig.EnableSSSE3())
+                        if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_SSE41) && JitConfig.EnableSSE41())
                         {
-                            opts.setSupportedISA(InstructionSet_SSSE3);
+                            opts.setSupportedISA(InstructionSet_SSE41);
+#ifdef _TARGET_AMD64_
+                            opts.setSupportedISA(InstructionSet_SSE41_X64);
+#endif // _TARGET_AMD64_
 
-                            if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_SSE41) && JitConfig.EnableSSE41())
+                            if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_SSE42) && JitConfig.EnableSSE42())
                             {
-                                opts.setSupportedISA(InstructionSet_SSE41);
+                                opts.setSupportedISA(InstructionSet_SSE42);
 #ifdef _TARGET_AMD64_
-                                opts.setSupportedISA(InstructionSet_SSE41_X64);
+                                opts.setSupportedISA(InstructionSet_SSE42_X64);
 #endif // _TARGET_AMD64_
 
-                                if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_SSE42) && JitConfig.EnableSSE42())
+                                if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_POPCNT) && JitConfig.EnablePOPCNT())
                                 {
-                                    opts.setSupportedISA(InstructionSet_SSE42);
+                                    opts.setSupportedISA(InstructionSet_POPCNT);
 #ifdef _TARGET_AMD64_
-                                    opts.setSupportedISA(InstructionSet_SSE42_X64);
+                                    opts.setSupportedISA(InstructionSet_POPCNT_X64);
 #endif // _TARGET_AMD64_
+                                }
+
+                                if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_AVX) && JitConfig.EnableAVX())
+                                {
+                                    opts.setSupportedISA(InstructionSet_AVX);
 
-                                    if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_POPCNT) && JitConfig.EnablePOPCNT())
+                                    if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_FMA) && JitConfig.EnableFMA())
                                     {
-                                        opts.setSupportedISA(InstructionSet_POPCNT);
-#ifdef _TARGET_AMD64_
-                                        opts.setSupportedISA(InstructionSet_POPCNT_X64);
-#endif // _TARGET_AMD64_
+                                        opts.setSupportedISA(InstructionSet_FMA);
                                     }
 
-                                    if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_AVX) && JitConfig.EnableAVX())
+                                    if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_AVX2) && JitConfig.EnableAVX2())
                                     {
-                                        opts.setSupportedISA(InstructionSet_AVX);
-
-                                        if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_FMA) && JitConfig.EnableFMA())
-                                        {
-                                            opts.setSupportedISA(InstructionSet_FMA);
-                                        }
-
-                                        if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_AVX2) && JitConfig.EnableAVX2())
-                                        {
-                                            opts.setSupportedISA(InstructionSet_AVX2);
-                                        }
+                                        opts.setSupportedISA(InstructionSet_AVX2);
                                     }
                                 }
                             }
@@ -2448,38 +2444,39 @@ void Compiler::compSetProcessor()
                     }
                 }
             }
+        }
 
-            if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_LZCNT) && JitConfig.EnableLZCNT())
-            {
-                opts.setSupportedISA(InstructionSet_LZCNT);
+        if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_LZCNT) && JitConfig.EnableLZCNT())
+        {
+            opts.setSupportedISA(InstructionSet_LZCNT);
 #ifdef _TARGET_AMD64_
-                opts.setSupportedISA(InstructionSet_LZCNT_X64);
+            opts.setSupportedISA(InstructionSet_LZCNT_X64);
 #endif // _TARGET_AMD64_
-            }
+        }
 
-            // We currently need to also check that AVX is supported as that controls the support for the VEX encoding
-            // in the emitter.
-            if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_BMI1) && JitConfig.EnableBMI1() &&
-                compSupports(InstructionSet_AVX))
-            {
-                opts.setSupportedISA(InstructionSet_BMI1);
+        // We currently need to also check that AVX is supported as that controls the support for the VEX encoding
+        // in the emitter.
+        if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_BMI1) && JitConfig.EnableBMI1() && compSupports(InstructionSet_AVX))
+        {
+            opts.setSupportedISA(InstructionSet_BMI1);
 #ifdef _TARGET_AMD64_
-                opts.setSupportedISA(InstructionSet_BMI1_X64);
+            opts.setSupportedISA(InstructionSet_BMI1_X64);
 #endif // _TARGET_AMD64_
-            }
+        }
 
-            // We currently need to also check that AVX is supported as that controls the support for the VEX encoding
-            // in the emitter.
-            if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_BMI2) && JitConfig.EnableBMI2() &&
-                compSupports(InstructionSet_AVX))
-            {
-                opts.setSupportedISA(InstructionSet_BMI2);
+        // We currently need to also check that AVX is supported as that controls the support for the VEX encoding
+        // in the emitter.
+        if (jitFlags.IsSet(JitFlags::JIT_FLAG_USE_BMI2) && JitConfig.EnableBMI2() && compSupports(InstructionSet_AVX))
+        {
+            opts.setSupportedISA(InstructionSet_BMI2);
 #ifdef _TARGET_AMD64_
-                opts.setSupportedISA(InstructionSet_BMI2_X64);
+            opts.setSupportedISA(InstructionSet_BMI2_X64);
 #endif // _TARGET_AMD64_
-            }
         }
+    }
 #else  // !FEATURE_CORECLR
+    if (!jitFlags.IsSet(JitFlags::JIT_FLAG_PREJIT))
+    {
         // If this is not FEATURE_CORECLR, the only flags supported by the VM are AVX and AVX2.
         // Furthermore, the only two configurations supported by the desktop JIT are SSE2 and AVX2,
         // so if the latter is set, we also check all the in-between options.
@@ -2501,8 +2498,8 @@ void Compiler::compSetProcessor()
             opts.setSupportedISA(InstructionSet_AVX);
             opts.setSupportedISA(InstructionSet_AVX2);
         }
-#endif // !FEATURE_CORECLR
     }
+#endif // !FEATURE_CORECLR
 
     if (!compIsForInlining())
     {