Simplify some relop/jtrue related optimizations

src/jit/codegenarm64.cpp

@@ -3298,40 +3298,6 @@ void CodeGen::genCodeForCompare(GenTreeOp* tree)
     assert(!op1->isUsedFromMemory());
     assert(!op2->isUsedFromMemory());
 
-    // Case of op1 == 0 or op1 != 0:
-    // Optimize generation of 'test' instruction if op1 sets flags.
-    //
-    // This behavior is designed to match the unexpected behavior
-    // of XARCH genCompareInt();
-    //
-    // TODO-Cleanup Review GTF_USE_FLAGS usage
-    // https://github.com/dotnet/coreclr/issues/14093
-    if ((tree->gtFlags & GTF_USE_FLAGS) != 0)
-    {
-        // op1 must set flags
-        assert(op1->gtSetFlags());
-
-        // Must be compare against zero.
-        assert(!tree->OperIs(GT_TEST_EQ, GT_TEST_NE));
-        assert(op2->IsIntegralConst(0));
-        assert(op2->isContained());
-
-        // Just consume the operands
-        genConsumeOperands(tree);
-
-        // No need to generate compare instruction since
-        // op1 sets flags
-
-        // Are we evaluating this into a register?
-        if (targetReg != REG_NA)
-        {
-            genSetRegToCond(targetReg, tree);
-            genProduceReg(tree);
-        }
-
-        return;
-    }
-
     genConsumeOperands(tree);
 
     emitAttr cmpSize = EA_ATTR(genTypeSize(op1Type));

src/jit/codegenxarch.cpp

@@ -887,7 +887,8 @@ void CodeGen::genCodeForBinary(GenTree* treeNode)
     }
 
     // try to use an inc or dec
-    if (oper == GT_ADD && !varTypeIsFloating(treeNode) && src->isContainedIntOrIImmed() && !treeNode->gtOverflowEx())
+    if (oper == GT_ADD && !varTypeIsFloating(treeNode) && src->isContainedIntOrIImmed() && !treeNode->gtOverflowEx() &&
+        !treeNode->gtSetFlags())
     {
         if (src->IsIntegralConst(1))
         {
@@ -6243,66 +6244,6 @@ void CodeGen::genCompareInt(GenTreePtr treeNode)
     var_types  op2Type   = op2->TypeGet();
     regNumber  targetReg = tree->gtRegNum;
 
-    // Case of op1 == 0 or op1 != 0:
-    // Optimize generation of 'test' instruction if op1 sets flags.
-    //
-    // TODO-Cleanup Review GTF_USE_FLAGS usage
-    // https://github.com/dotnet/coreclr/issues/14093
-    //
-    // Note that if LSRA has inserted any GT_RELOAD/GT_COPY before
-    // op1, it will not modify the flags set by codegen of op1.
-    // Similarly op1 could also be reg-optional at its use and
-    // it was spilled after producing its result in a register.
-    // Spill code too will not modify the flags set by op1.
-    GenTree* realOp1 = op1->gtSkipReloadOrCopy();
-    if ((tree->gtFlags & GTF_USE_FLAGS) != 0)
-    {
-        // op1 must set ZF and SF flags
-        assert(realOp1->gtSetZSFlags());
-        assert(realOp1->gtSetFlags());
-
-        // Must be (in)equality against zero.
-        assert(tree->OperIs(GT_EQ, GT_NE));
-        assert(op2->IsIntegralConst(0));
-        assert(op2->isContained());
-
-        // Just consume the operands
-        genConsumeOperands(tree);
-
-        // No need to generate test instruction since
-        // op1 sets flags
-
-        // Are we evaluating this into a register?
-        if (targetReg != REG_NA)
-        {
-            genSetRegToCond(targetReg, tree);
-            genProduceReg(tree);
-        }
-
-        return;
-    }
-
-#ifdef FEATURE_SIMD
-    // If we have GT_JTRUE(GT_EQ/NE(GT_SIMD((in)Equality, v1, v2), true/false)),
-    // then we don't need to generate code for GT_EQ/GT_NE, since SIMD (in)Equality intrinsic
-    // would set or clear Zero flag.
-    if ((targetReg == REG_NA) && tree->OperIs(GT_EQ, GT_NE))
-    {
-        // Is it a SIMD (in)Equality that doesn't need to materialize result into a register?
-        if ((op1->gtRegNum == REG_NA) && op1->IsSIMDEqualityOrInequality())
-        {
-            // Must be comparing against true or false.
-            assert(op2->IsIntegralConst(0) || op2->IsIntegralConst(1));
-            assert(op2->isContainedIntOrIImmed());
-
-            // In this case SIMD (in)Equality will set or clear
-            // Zero flag, based on which GT_JTRUE would generate
-            // the right conditional jump.
-            return;
-        }
-    }
-#endif // FEATURE_SIMD
-
     genConsumeOperands(tree);
 
     assert(!op1->isContainedIntOrIImmed());

src/jit/compiler.cpp

@@ -9781,11 +9781,11 @@ int cTreeFlagsIR(Compiler* comp, GenTree* tree)
         {
             chars += printf("[SPILLED_OP2]");
         }
-#endif
         if (tree->gtFlags & GTF_ZSF_SET)
         {
             chars += printf("[ZSF_SET]");
         }
+#endif
 #if FEATURE_SET_FLAGS
         if (tree->gtFlags & GTF_SET_FLAGS)
         {

src/jit/gentree.h

@@ -856,11 +856,11 @@ struct GenTree
 #ifdef LEGACY_BACKEND
 #define GTF_SPILLED_OPER 0x00000100 // op1 has been spilled
 #define GTF_SPILLED_OP2  0x00000200 // op2 has been spilled
+#define GTF_ZSF_SET      0x00000400 // the zero(ZF) and sign(SF) flags set to the operand
 #else  // !LEGACY_BACKEND
 #define GTF_NOREG_AT_USE 0x00000100 // tree node is in memory at the point of use
 #endif // !LEGACY_BACKEND
 
-#define GTF_ZSF_SET     0x00000400 // the zero(ZF) and sign(SF) flags set to the operand
 #define GTF_SET_FLAGS   0x00000800 // Requires that codegen for this node set the flags. Use gtSetFlags() to check this flag.
 #define GTF_USE_FLAGS   0x00001000 // Indicates that this node uses the flags bits.
 
@@ -2126,12 +2126,14 @@ struct GenTree
     bool gtSetFlags() const;
     bool gtRequestSetFlags();
 
+#ifdef LEGACY_BACKEND
     // Returns true if the codegen of this tree node
     // sets ZF and SF flags.
     bool gtSetZSFlags() const
     {
         return (gtFlags & GTF_ZSF_SET) != 0;
     }
+#endif
 
 #ifdef DEBUG
     bool       gtIsValid64RsltMul();