package com.seaofnodes.simple;
import com.seaofnodes.simple.node.*;
import com.seaofnodes.simple.type.*;


import com.seaofnodes.simple.codegen.CodeGen;
import org.junit.Ignore;
import org.junit.Test;
import static com.seaofnodes.simple.Main.PORTS;
import static org.junit.Assert.*;
import static org.junit.Assert.fail;

public class Chapter19Test {
    @Test public void testPrintingFunctionLookup() {
        var code = new CodeGen("return 0;").parse();
        var tfp = TypeFunPtr.make((byte)2,TypeTuple.make(TypeInteger.constant(987654)),TypeInteger.constant(123456),1L<<30);
        var con = new ConstantNode(tfp);
        var call = new CallNode(null,code._start,con,con);
        // Diagnostic lookup may construct/intern the return-erased linker key.
        con.toString();
        org.junit.Assert.assertNull(call.name());

        var fun = new FunNode(null,tfp);
        fun._name = "printerTarget";
        fun.addDef(code._start);
        code.link(fun);
        var otherReturn = tfp.makeFrom(TypeInteger.constant(654321));
        org.junit.Assert.assertSame(fun,code.link(otherReturn));
        org.junit.Assert.assertTrue(con.toString().contains("printerTarget"));
        assertEquals("printerTarget",call.name());
    }


    @Ignore
    @Test
    public void testJig() {
        CodeGen code = new CodeGen("""
return 0;
""");
        code.parse().opto().typeCheck();
        assertEquals("return 0;", code._stop.toString());
        assertEquals("0", Eval2.eval(code,  2));
    }


    @Test
    public void testString() {
        CodeGen code = new CodeGen(
"""
struct String {
    u8[] !cs;
    int _hashCode;
};

val equals = { !String !self, !String s ->
    if( self == s ) return true;
    if( self.cs# != s.cs# ) return false;
    for( int i=0; i< self.cs#; i++ )
        if( self.cs[i] != s.cs[i] )
            return false;
    return true;
};

val hashCode = { !String self ->
    self._hashCode
    ?  self._hashCode
    : (self._hashCode = _hashCodeString(self));
};

val _hashCodeString = { !String self ->
    int hash=0;
    if( self.cs ) {
        for( int i=0; i< self.cs#; i++ )
            hash = hash*31 + self.cs[i];
    }
    if( !hash ) hash = 123456789;
    return hash;
};

!String !s = new String { cs = new u8[17]; };
s.cs[0] =  67; // C
s.cs[1] = 108; // l
hashCode(s)+hashCode(s);""");
        code.parse().opto().typeCheck().GCM().localSched();
        assertEquals("Stop[ return (#2+#2); return Phi(Region,1,0,0,1); return Phi(Region,._hashCode,Phi(Region,123456789,Phi(Loop,0,(.[]+((Phi_hash<<5)-Phi_hash))))); ]", code._stop.toString());
        assertEquals("-4898613127354160978", Eval2.eval(code,  2));
    }

    @Test
    public void testBasic0() {
        CodeGen code = new CodeGen("return 0;").parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return 0;", code._stop.toString());
    }

    @Test
    public void testBasic1() {
        CodeGen code = new CodeGen("return arg+1;").parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (inc,arg);", code._stop.toString());
    }

    @Test
    public void testBasic2() {
        CodeGen code = new CodeGen("return -17;").parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return -17;", code._stop.toString());
    }


    @Test
    public void testBasic3() {
        CodeGen code = new CodeGen("return arg==1;").parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (set==,(cmp,arg));", code._stop.toString());
    }

    @Test
    public void testBasic4() {
        CodeGen code = new CodeGen("return arg<<1;").parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (shli,arg);", code._stop.toString());
    }

    @Test
    public void testBasic5() {
        CodeGen code = new CodeGen("return arg >> 1;").parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (sari,arg);", code._stop.toString());
    }

    @Test
    public void testBasic6() {
        CodeGen code = new CodeGen("return arg >>> 1;").parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (shri,arg);", code._stop.toString());
    }

    @Test
    public void testBasic7() {
        CodeGen code = new CodeGen("return arg / 2;").parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (div,arg,2);", code._stop.toString());
    }

    @Test
    public void testBasic8() {
        CodeGen code = new CodeGen("return arg * 6;").parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (muli,arg);", code._stop.toString());
    }

    @Test
    public void testBasic9() {
        CodeGen code = new CodeGen("return arg & 2;").parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (andi,arg);", code._stop.toString());
    }

    @Test
    public void testBasic10() {
        CodeGen code = new CodeGen("return arg | 2;").parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (ori,arg);", code._stop.toString());
    }

    @Test
    public void testBasic11() {
        CodeGen code = new CodeGen("return arg ^ 2;").parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (xori,arg);", code._stop.toString());
    }

    @Test
    public void testBasic12() {
        CodeGen code = new CodeGen("return arg + 2.0;").parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (addf,(i2f8,arg),2.0f);", code._stop.toString());
    }

    @Test
    public void testBasic13() {
        CodeGen code = new CodeGen("return arg - 2.0;").parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (subf,(i2f8,arg),2.0f);", code._stop.toString());
    }

    @Test
    public void testBasic14() {
        CodeGen code = new CodeGen("return arg * 2.0;").parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (mulf,(i2f8,arg),2.0f);", code._stop.toString());
    }

    @Test
    public void testBasic15() {
        CodeGen code = new CodeGen("return arg / 2.0;").parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (mulf,(i2f8,arg),0.5f);", code._stop.toString());
    }

    @Test
    public void testBasic16() {
        CodeGen code = new CodeGen(
"""
int arg1 =  arg + 1;
return arg1 / arg;""");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (div,(inc,arg),arg);", code._stop.toString());
    }

    @Test
    public void testBasic17() {
        CodeGen code = new CodeGen(
"""
int arg1 =  arg + 1;
return arg1 * arg;
""");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (mul,(inc,arg),arg);", code._stop.toString());
    }

    @Test
    public void testToFloat() {
        CodeGen code = new CodeGen("""
                int a = arg;
                return a + 2.0;
                """
        ).parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (addf,(i2f8,arg),2.0f);", code._stop.toString());
    }

    @Test
    public void testIfStmt() {
        CodeGen code = new CodeGen(
"""
int a = 1;
if (arg == 1)
    a = arg+2;
else {
    a = arg-3;
}
return a;""");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return Phi(Region,(addi,arg),(addi,arg));", code.print());
    }

    @Test
    public void testIfMerge2() {
        CodeGen code = new CodeGen(
"""
int a=arg+1;
int b=arg+2;
if( arg==1 )
    b=b+a;
else
    a=b+1;
return a+b;""");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (add,(add,Phi(Region,(shli,arg),arg),arg),Phi(Region,4,5));", code.print());
    }

    @Test
    public void testLoop() {
        CodeGen code = new CodeGen(
"""
int sum=0;
for( int i=0; i<arg; i++ )
    sum += i;
return sum;""");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return Phi(Loop,0,(add,Phi_sum,Phi(Loop,0,(inc,Phi_i))));", code.print());
    }

    @Test
    public void testAlloc1() {
        CodeGen code = new CodeGen(
"""
struct S { int a; !S? !c; };
return new S;""");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return S;", code.print());
    }

    @Test
    public void testLea1() {
        CodeGen code = new CodeGen("int x = arg/3; return arg+x+7;");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2",  "SystemV").GCM().localSched();
        assertEquals("return (lea,arg,(div,arg,3));", code.print());
    }

    @Test
    public void testLea2() {
        CodeGen code = new CodeGen("int x = arg/3; return arg+x*4+7;");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return (lea,arg,(div,arg,3));", code.print());
    }

    @Test
    public void testLea3() {
        CodeGen code = new CodeGen("int x = arg/3; return x*4+arg;");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2",  "SystemV").GCM().localSched();
        assertEquals("return (lea,arg,(div,arg,3));", code.print());
    }

    @Test
    public void testAlloc2() {
        CodeGen code = new CodeGen("int[] !xs = new int[3]; xs[arg]=1; return xs[arg&1];");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return .[];", code.print());
    }

    @Test
    public void testAlloc3() {
        CodeGen code = new CodeGen("int[] !xs = new int[3]; xs[arg]=1; return xs[arg&1]+3;");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return .[];", code.print());
    }

    @Test
    public void testArray1() {
        CodeGen code = new CodeGen(
"""
int[] !ary = new int[arg];
// Fill [0,1,2,3,4,...]
for( int i=0; i<ary#; i++ )
    ary[i] = i;
// Fill [0,1,3,6,10,...]
for( int i=0; i<ary#-1; i++ )
    ary[i+1] += ary[i];
return ary[1] * 1000 + ary[3]; // 1 * 1000 + 6
""");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return .[];", code.print());
    }

    @Test
    public void testArray2() {
        CodeGen code = new CodeGen(
"""
flt[] !A = new flt[arg], !B = new flt[arg];
// Fill [0,1,2,3,4,...]
for( int i=0; i<A#; i++ )
    A[i] = i;
for( int i=0; i<A#; i++ )
    B[i] += A[i];
""");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return 0;", code.print());
    }

    @Test
    public void testArray3() {
        CodeGen code = new CodeGen(
"""
byte[] !A = new byte[arg];
for( int i=0; i<A#; i++ )
    A[i]++;
return A[1];
""");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return .[];", code.print());
    }

    @Test
    public void testNewton() {
        CodeGen code = new CodeGen(
"""
// Newtons approximation to the square root
val sqrt = { flt x ->
    flt guess = x;
    while( 1 ) {
        flt next = (x/guess + guess)/2;
        if( next == guess ) return guess;
        guess = next;
    }
};
flt farg = arg;
return sqrt(farg);
""");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return Phi(Loop,(i2f8,arg),(mulf,(addf,(divf,i2f8,Phi_guess),Phi_guess),0.5f));", code.print());
    };


    @Test
    public void sieveOfEratosthenes() {
        CodeGen code = new CodeGen(
"""
var ary = new bool[arg], primes = new int[arg];
var nprimes=0, p=0;
// Find primes while p^2 < arg
for( p=2; p*p < arg; p++ ) {
    // skip marked non-primes
    while( ary[p] ) p++;
    // p is now a prime
    primes[nprimes++] = p;
    // Mark out the rest non-primes
    for( int i = p + p; i < ary#; i += p )
        ary[i] = true;
}
// Now just collect the remaining primes, no more marking
for( ; p < arg; p++ )
    if( !ary[p] )
        primes[nprimes++] = p;
// Copy/shrink the result array
var !rez = new int[nprimes];
for( int j=0; j<nprimes; j++ )
    rez[j] = primes[j];
return rez;
""");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("return [int];", code.print());
        //assertEquals("int[ 2,3,5,7,11,13,17,19]",Eval2.eval(code, 20));
    }


    @Test
    public void testFcn1() {
        CodeGen code = new CodeGen(
"""
val fcn = arg ? { int x -> x*x; } : { int x -> x+x; };
return fcn(2)*10 + fcn(3);
""");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("Stop[ return (add,#2,(muli,#2)); return (mul,Parm_x($fun1,int),x); return (shli,Parm_x($fun2,int)); ]", code.print());
    }

    @Test
    public void testFcn2() {
        CodeGen code = new CodeGen(
"""
val sq = { int x -> x*x; };
return sq(arg) + sq(3);
""");
        code.parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2", "SystemV").GCM().localSched();
        assertEquals("Stop[ return (add,#2,#2); return (mul,Parm_x(sq,int),x); ]", code.print());
    }

    @Test public void testSelectedMemory() {
        for( String cpu : new String[]{"x86_64_v2","riscv","arm"} )
            for( String src : new String[]{Chapter10Test.NESTED_MEMORY,Chapter16Test.CONSTRUCTOR_MEMORY,
                                          Chapter18Test.CALL_MEMORY,Chapter18Test.RECURSIVE_MEMORY} ) {
                var code = new CodeGen(src).parse().opto().typeCheck();
                var aliases = memoryPhis(code._stop);
                code.instSelect(PORTS,cpu,"SystemV");
                assertEquals(aliases,memoryPhis(code._stop));
                code.GCM().localSched();
                code._stop.walk(n -> {
                    if( !(n instanceof CFGNode) && !(n instanceof ProjNode) )
                        assertTrue(n.in(0) instanceof CFGNode);
                    if( n instanceof NewNode nn ) {
                        assertEquals(2,((TypeTuple)nn._type)._types.length);
                        assertTrue(nn.mem() instanceof MemMergeNode);
                        assertNull(nn.mem().in(1)); // Partial allocation input.
                        MachNode mach = (MachNode)nn;
                        assertNull(mach.regmap(1));
                        assertNotNull(mach.regmap(2));
                        assertNotNull(mach.outregmap(0));
                        assertNull(mach.outregmap(1));
                    }
                    if( n instanceof CallNode call ) {
                        assertEquals(4,call.nIns()); // ctrl, memory, two args; direct target is embedded.
                    }
                    return null;
                });
            }
    }

    private static java.util.ArrayList<String> memoryPhis(Node stop) {
        var phis = new java.util.ArrayList<String>();
        // Count only definitions reachable from Stop, as instruction selection does.
        // A dead Phi cycle can still appear through the reverse use edges.
        var seen = new java.util.BitSet();
        var work = new java.util.ArrayList<Node>();
        work.add(stop);
        for( int i=0; i<work.size(); i++ ) {
            Node n = work.get(i);
            if( n==null || seen.get(n._nid) ) continue;
            seen.set(n._nid);
            for( Node def : n._inputs ) work.add(def);
            if( n instanceof MemPhiNode phi ) phis.add("alias:"+phi._alias);
            if( n instanceof BulkMemPhiNode phi ) phis.add("bulk:"+phi._aliases);
            assertFalse(n instanceof PhiNode && n.isMem() &&
                !(n instanceof MemPhiNode) && !(n instanceof BulkMemPhiNode) && !(n instanceof ParmNode));
        }
        java.util.Collections.sort(phis);
        return phis;
    }

    @Test public void testFoldedReadBeforeWrites() {
        var code = new CodeGen("""
            struct S { int x; };
            !S !a = new S { x=11; }; !S !b = new S { x=22; };
            !S !p = a; if( arg ) p = b;
            int before = p.x + arg;
            a.x=33; b.x=44;
            return before;
            """).parse().opto().typeCheck().instSelect(PORTS,"x86_64_v2","SystemV").GCM().localSched();
        var read = (MemOpNode)code._stop.walk(n ->
            n instanceof com.seaofnodes.simple.node.cpus.x86_64_v2.AddMemX86 ? n : null);
        assertNotNull(read);
        int writes = 0;
        for( Node use : read.antiDeps() )
            if( use instanceof MemOpNode st && st.isMem() ) {
                assertSame(read.cfg0(),st.cfg0());
                assertTrue(st._inputs.find(read)>=0);
                assertTrue(read.cfg0()._outputs.find(read)<st.cfg0()._outputs.find(st));
                assertNull(((MachNode)st).regmap(st._inputs.find(read)));
                writes++;
            }
        assertEquals(1,writes); // The next Store follows this first clobber through memory.
    }
}