Fix parameter ordering and value in gtNewColonNode

[huoyaoyuan]

To match the constructor parameters of GenTreeColon.

All of the callers are passing arguments in the correct order. The 64 bit BSR implementation of LZCNT gets an int colon instead of long. Since the result is <64, there wasn't incorrect truncation if JIT is tolerate to such type mismatch.

[ghost]

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Issue Details

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To match the constructor parameters of GenTreeColon.

All of the callers are passing arguments in the correct order. The 64 bit BSR implementation of LZCNT gets an int colon instead of long. Since the result is <64, there wasn't incorrect truncation if JIT is tolerate to such type mismatch.

Author:	huoyaoyuan
Assignees:	-
Labels:	area-CodeGen-coreclr, community-contribution
Milestone:	-

[EgorBo]

Does this fix a bug or something? The problem that ElseNode is op1 so it just adds more confusion where we already have it. A proper fix might require more changes

runtime/src/coreclr/jit/gentree.h

Lines 3956 to 3970 in 66def3a

	// There was quite a bit of confusion in the code base about which of gtOp1 and gtOp2 was the
	// 'then' and 'else' clause of a colon node. Adding these accessors, while not enforcing anything,
	// at least *allows* the programmer to be obviously correct.
	// However, these conventions seem backward.
	// TODO-Cleanup: If we could get these accessors used everywhere, then we could switch them.
	struct GenTreeColon : public GenTreeOp
	{
	GenTree*& ThenNode()
	{
	return gtOp2;
	}
	GenTree*& ElseNode()
	{
	return gtOp1;
	}

(see comment)

cc @dotnet/jit-contrib

[huoyaoyuan]

This fixes my confusion when trying to use gtNewColonNode instead of new (this, GT_COLON) GenTreeColon.

runtime/src/coreclr/jit/gentree.h

Lines 3978 to 3980 in 66def3a

	GenTreeColon(var_types typ, GenTree* thenNode, GenTree* elseNode) : GenTreeOp(GT_COLON, typ, elseNode, thenNode)
	{
	}

The parameter names in GenTreeColon constructor are correct, but gtNewColonNode is incorrect. thenNode is correctly stored into op2.