From d32f97238c903765dec4e9a9f3cbfa5fd12cded6 Mon Sep 17 00:00:00 2001 From: Cliff Click Date: Mon, 10 Aug 2026 11:11:18 -0700 Subject: Chapter 25: Modules, Separate Compilation, and SSA Construction Co-authored-by: Hsiang-Ying Fu <66062782+fuhsnn@users.noreply.github.com> Co-authored-by: fuhsnn <66062782+fuhsnn@users.noreply.github.com> Co-authored-by: Symious <14933944+symious@users.noreply.github.com> Co-authored-by: Jun Kawasaki Co-authored-by: Claude Opus 5 --- .../com/seaofnodes/simple/node/ConvertNode.java | 101 +++++++++++++++++++++ 1 file changed, 101 insertions(+) create mode 100644 src/main/java/com/seaofnodes/simple/node/ConvertNode.java (limited to 'src/main/java/com/seaofnodes/simple/node/ConvertNode.java') diff --git a/src/main/java/com/seaofnodes/simple/node/ConvertNode.java b/src/main/java/com/seaofnodes/simple/node/ConvertNode.java new file mode 100644 index 00000000..b6c3b0c9 --- /dev/null +++ b/src/main/java/com/seaofnodes/simple/node/ConvertNode.java @@ -0,0 +1,101 @@ +package com.seaofnodes.simple.node; + +import com.seaofnodes.print.ExprPrinter; + +import com.seaofnodes.simple.Parser; +import com.seaofnodes.simple.codegen.CodeGen; +import com.seaofnodes.simple.type.*; + +import java.util.HashMap; + +// Convert a value to an authoritative destination type. The destination is +// known structurally from a declaration; the source family might sharpen later. +public class ConvertNode extends Node { + private Type _dst; + + public ConvertNode(Type dst, Node val) { + super(null,val); + // Folding this conversion would replace the Return-linked FunPtrNode + // with an unhooked ConstantNode. + assert !(dst instanceof TypeFunPtr && val instanceof FunPtrNode); + _dst = dst; + } + + public Type dst() { return _dst; } + public Node val() { return in(1); } + + @Override public String label() { return "Convert_"+_dst.str(); } + @Override protected ExprPrinter _print1(ExprPrinter p) { + return p.p(label()).open().n(val()).close(); + } + + // The declaration fixes the result family during pessimistic parsing. + // Optimistic SCCP must retain stronger facts already inside that family. + @Override public Type compute() { + Type src = val()._type; + if( CodeGen.CODE._phase == CodeGen.Phase.Opto ) { + if( src.isHigh() ) return Type.TOP; + if( (src.isa(_dst) && src.accessISA(_dst)) ) return src; + } + return _dst; + } + + @Override public Node idealize() { + Type src = val()._type; + if( src==Type.BOTTOM || src==Type.TOP ) return null; + if( (src.isa(_dst) && src.accessISA(_dst)) ) return val(); + + // Managed arrays are represented by an object pointer, while C wants + // the address of the first element. The representation cast itself is + // zero-code; the Add skips the array header. + if( _dst==TypeInteger.BOT && src instanceof TypeMemPtr tmp && tmp._obj.isAry() ) + return new AddNode(new PtrToIntNode(val()).peephole(),Parser.off(tmp._obj,"[]")); + + // Integer (and nil-as-zero) to floating point. + if( (src instanceof TypeInteger || src==Type.NIL) && _dst instanceof TypeFloat ) + return new ToFloatNode(val()); + + // Convert to i64 first, then apply the destination's integer width. + if( src instanceof TypeFloat && _dst instanceof TypeInteger ) + return new ConvertNode(_dst,new ToIntegerNode(val()).peephole()); + + // Narrow integers produce the declared sign/zero extension. + if( src instanceof TypeInteger && _dst instanceof TypeInteger dst ) { + if( dst._min==0 ) + return new AndNode(null,val(),con(dst._max)); + int shift = Long.numberOfLeadingZeros(dst._max)-1; + Node shf = con(shift); + if( shf._type==TypeInteger.ZERO ) return val(); + return new SarNode(null,new ShlNode(null,val(),shf.keep()).peephole(),shf.unkeep()); + } + + // Narrow f64 to f32. + if( src instanceof TypeFloat && _dst instanceof TypeFloat ) + return new RoundF32Node(val()); + + // Wait for more source information, or report an error after Opto. + return null; + } + + @Override boolean _upgradeType(HashMap TYPES) { + Type dst = _dst.upgradeType(TYPES); + if( dst==_dst ) return false; + unlock(); + _dst = dst; + return true; + } + + @Override public Parser.ParseException err() { + if( val()._type==Type.BOTTOM || + val()._type instanceof TypeNil src && src.nullable() && _dst instanceof TypeNil dst && dst.notNull() ) { + Node out = out(0); + if( out instanceof PhiNode phi ) out = phi.out(0); + if( out instanceof StoreNode st ) + return Parser.error( "'" + ((TypeMemPtr)st.ptr()._type)._obj._name + "' is not fully initialized, field '" + st._name + "' is only partially set in the constructor", null ); + } + return Parser.error("Type "+val()._type.str()+" is not of declared type "+_dst.str(),null); + } + + @Override public boolean eq(Node n) { return _dst==((ConvertNode)n)._dst; } + @Override int hash() { return _dst.hashCode(); } +} -- cgit v1.2.3