fix

Author: VSadov

src/coreclr/jit/codegencommon.cpp

@@ -502,9 +502,14 @@ void CodeGenInterface::genUpdateLife(GenTree* tree)
     treeLifeUpdater->UpdateLife(tree);
 }
 
-bool CodeGenInterface::genUpdateLife(VARSET_VALARG_TP newLife)
+void CodeGenInterface::genUpdateLife(VARSET_VALARG_TP newLife)
 {
-    return compiler->compUpdateLife</*ForCodeGen*/ true>(newLife);
+    compiler->compUpdateLife</*ForCodeGen*/ true>(newLife);
+}
+
+bool CodeGenInterface::genWillUpdateLife(VARSET_VALARG_TP newLife)
+{
+    return compiler->compWillUpdateLife(newLife);
 }
 
 // Return the register mask for the given register variable

src/coreclr/jit/codegeninterface.h

@@ -165,7 +165,8 @@ class CodeGenInterface
     regMaskTP genGetRegMask(GenTree* tree);
 
     void genUpdateLife(GenTree* tree);
-    bool genUpdateLife(VARSET_VALARG_TP newLife);
+    void genUpdateLife(VARSET_VALARG_TP newLife);
+    bool genWillUpdateLife(VARSET_VALARG_TP newLife);
 
     TreeLifeUpdater<true>* treeLifeUpdater;
 

src/coreclr/jit/codegenlinear.cpp

@@ -192,21 +192,22 @@ void CodeGen::genCodeForBBlist()
 
         compiler->m_pLinearScan->recordVarLocationsAtStartOfBB(block);
 
-        // Updating variable liveness after last instruction of previous block was emitted
-        // and before first of the current block is emitted
-        bool livenessChanged = genUpdateLife(block->bbLiveIn);
-
-        // if liveness has changed and the last block ended on emitting a call that can do GC,
+        // if liveness is changing and the last block ended on emitting a call that can do GC,
         // emit a nop to ensure that GC info is not changing between
         // "call has been made" and "call has returned" states.
-        if (livenessChanged)
+        if (genWillUpdateLife(block->bbLiveIn))
         {
             if (GetEmitter()->emitLastInsIsCallWithGC())
             {
+                printf("####################\n");
                 instGen(INS_nop);
             }
         }
 
+        // Updating variable liveness after last instruction of previous block was emitted
+        // and before first of the current block is emitted
+        genUpdateLife(block->bbLiveIn);
+
         // Even if liveness didn't change, we need to update the registers containing GC references.
         // genUpdateLife will update the registers live due to liveness changes. But what about registers that didn't
         // change? We cleared them out above. Maybe we should just not clear them out, but update the ones that change

src/coreclr/jit/compiler.h

@@ -8516,7 +8516,12 @@ class Compiler
     // Update the GC's masks, register's masks and reports change on variable's homes given a set of
     // current live variables if changes have happened since "compCurLife".
     template <bool ForCodeGen>
-    inline bool compUpdateLife(VARSET_VALARG_TP newLife);
+    inline void compUpdateLife(VARSET_VALARG_TP newLife);
+
+    inline bool compWillUpdateLife(VARSET_VALARG_TP newLife)
+    {
+        return (!VarSetOps::Equal(this, compCurLife, newLife));
+    }
 
     // Gets a register mask that represent the kill set for a helper call since
     // not all JIT Helper calls follow the standard ABI on the target architecture.

src/coreclr/jit/compiler.hpp

@@ -3543,12 +3543,11 @@ XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
 //    The set of live variables reflects the result of only emitted code, it should not be considering the becoming
 //    live/dead of instructions that has not been emitted yet. This is requires by "compChangeLife".
 template <bool ForCodeGen>
-inline bool Compiler::compUpdateLife(VARSET_VALARG_TP newLife)
+inline void Compiler::compUpdateLife(VARSET_VALARG_TP newLife)
 {
     if (!VarSetOps::Equal(this, compCurLife, newLife))
     {
         compChangeLife<ForCodeGen>(newLife);
-        return true;
     }
 #ifdef DEBUG
     else
@@ -3561,8 +3560,6 @@ inline bool Compiler::compUpdateLife(VARSET_VALARG_TP newLife)
         }
     }
 #endif // DEBUG
-
-    return false;
 }
 
 /*****************************************************************************