changeset 2997:a100e097a675

Remove obsolete graph building documentation.
author Thomas Wuerthinger <thomas@wuerthinger.net>
date Thu, 16 Jun 2011 14:21:40 +0200
parents 4025f436a2e4
children 775881292ddb
files graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/graph/package-info.java
diffstat 1 files changed, 0 insertions(+), 123 deletions(-) [+]
line wrap: on
line diff
--- a/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/graph/package-info.java	Thu Jun 16 14:20:20 2011 +0200
+++ b/graal/com.oracle.max.graal.compiler/src/com/oracle/max/graal/compiler/graph/package-info.java	Thu Jun 16 14:21:40 2011 +0200
@@ -27,128 +27,5 @@
  * The {@link com.oracle.max.graal.compiler.graph.IR} class drives the generation of the HIR graph for a method, making use of other
  * utility classes in this package.
  *
- * The graph building is separated into a basic build phase ({@link com.oracle.max.graal.compiler.graph.IR#buildGraph} method)and
- * (currently) two optimization phases ({@link com.oracle.max.graal.compiler.graph.IR#optimize1} and
- * {@link com.oracle.max.graal.compiler.graph.IR#optimize2}) although the basic phase also does some (basic) optimizations.
- *
- * <H2>Basic Graph Build Phase</H2>
- *
- * {@code IR.buildGraph} creates an {@link com.oracle.max.graal.compiler.ir.IRScope topScope} object,
- * that represents a context for inlining, and then invokes the constructor for the
- * {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase} class, passing the {@link com.oracle.max.graal.compiler.GraalCompilation}, and {@code IR}
- * instances, which are cached. The following support objects are created in the constructor:
- *
- * <ul>
- * <li>{@code memoryMap}: an instance of {@link com.oracle.max.graal.compiler.graph.MemoryMap}
- * <li>{@code localValueMap}: an instance of {@link com.oracle.max.graal.compiler.opt.ValueMap}
- * <li>{@code canonicalizer}: an instance of {@link com.oracle.max.graal.compiler.opt.Canonicalizer}
- * </ul>
- *
- * Now the {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#build} is invoked with {@code topScope} as argument.
- *
- * <H3>{@code GraphBuilder.build}</H3>
- *
- * <ol>
- * <li>The {@link com.oracle.max.graal.compiler.graph.IR#startBlock} field of the cached {@link com.oracle.max.graal.compiler.graph.IR} instance is set to a newly created
- * {@link com.oracle.max.graal.compiler.ir.BlockBegin} node, with bytecode index 0 and then the {@link com.oracle.max.graal.compiler.graph.BlockMap} is
- * constructed by calling {@link com.oracle.max.graal.compiler.GraalCompilation#getBlockMap}. This behaves slightly differently depending on
- * whether this is an OSR compilation. If so, a new {@link com.oracle.max.graal.compiler.ir.BlockBegin} node is added to the map at the OSR bytecode
- * index. The map is then built by the{@link com.oracle.max.graal.compiler.graph.BlockMap#build}, which takes a boolean argument that
- * controls whether a second pass is made over the bytecodes to compute stores in loops. This always false for an OSR
- * compilation (why?). Otherwise, it is only true if enabled by the {@link com.oracle.max.graal.compiler.GraalOptions#PhiLoopStores}
- * compilation option. FInally some unneeded state from the map is removed by the {@link com.oracle.max.graal.compiler.graph.BlockMap#cleanup} method, and
- * the statistics are updated.
- * </li>
- *
- * <li>Next the {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#pushRootScope} method is called, with the passed-in {@link com.oracle.max.graal.compiler.ir.IRScope}
- * object, the {@link com.oracle.max.graal.compiler.graph.BlockMap} returned by build and the {@code startBlock}. (Note: Unlike
- * {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#pushScope}, this method does not propagate the
- * {@link com.oracle.max.graal.compiler.graph.BlockMap#storesInLoops} field to the {@link com.oracle.max.graal.compiler.ir.IRScope} object, which means that
- * {@link com.oracle.max.graal.compiler.ir.BlockBegin#insertLoopPhis} will always get null for this value. Is this a bug?).
- * {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#pushRootScope} initializes the {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#scopeData} field with a
- * {@link com.oracle.max.graal.compiler.graph.ScopeData} instance, with null parent. The
- * {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#compilation} instance is called to get an {@link com.sun.cri.ri.RiConstantPool}
- * , which is Graal's interface to constant pool information. The {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#curBlock} field is
- * set to the {@code startBlock}.
- * <p>
- *
- * Now a {@link com.oracle.max.graal.compiler.value.FrameState initialState} object is created by
- * {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#stateAtEntry}. If the method is not static, then a {@link com.oracle.max.graal.compiler.ir.Local}
- * instance is created at index 0. Since the receiver cannot be {@code null}, the
- * {@link com.oracle.max.graal.compiler.ir.Value.Flag#NonNull} flag is set. Additional {@link com.oracle.max.graal.compiler.ir.Local} instances are created for the
- * arguments to the method. The index is incremented by the number of slots occupied by the
- * {@link com.sun.cri.ci.CiKind} corresponding to the argument type. All the {@link com.oracle.max.graal.compiler.ir.Local} instances are stored in the
- * {@link com.oracle.max.graal.compiler.value.FrameState} using the {@link com.oracle.max.graal.compiler.value.FrameState#storeLocal} method. This {@link com.oracle.max.graal.compiler.value.FrameState} is then
- * merged into the {@link com.oracle.max.graal.compiler.ir.BlockBegin#stateBefore} for the {@code startBlock}, which just results in a
- * copy since {@code stateBefore} will be {@code null}.
- * </li>
- * <li>
- * This step sets up three instance fields: {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#curBlock} and
- * {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#lastInstr} to {@code startBlock} and
- * {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#curState} to {@code initialState}. (N.B. the setting of {@code curBlock} is
- * redundant as it is done in {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#pushRootScope}).
- * </li>
- * <li>
- * Step 4 contains special handling for synchronized methods (TBD), otherwise it calls
- * {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#finishStartBlock} which adds a {@link com.oracle.max.graal.compiler.ir.Base} block as the end of
- * the {@code startBlock}. The {@link com.oracle.max.graal.compiler.ir.Base} block has one successor set to the (entry) block with flag
- * {@link com.oracle.max.graal.compiler.ir.BlockBegin.BlockFlag#StandardEntry}, that was created by {@link com.oracle.max.graal.compiler.graph.BlockMap#build} (and possibly a
- * successor to an OSREntry block).
- * </li>
- * <li>
- * Then the {@link com.oracle.max.graal.compiler.ir.IRScope#lockStackSize} is computed. (TBD)
- * </li>
- * <li>
- * Then the method is checked for being intrinsic, i.e., one that has a hard-wired implementation known to Graal. If so,
- * and {@link com.oracle.max.graal.compiler.GraalOptions#OptIntrinsify} is set, an attempt is made to inline it (TBD). Otherwise, or if the
- * intrinsification fails, normal processing continues by adding the entry block to the
- * {@link com.oracle.max.graal.compiler.graph.ScopeData} work list (kept topologically sorted) and calling
- * {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#iterateAllBlocks}.
- * </li>
- * <li>
- * Finally there is some cleanup code for synchronized blocks and OSR compilations.
- * </li>
- * </ol>
- *
- * <H3>{@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#iterateAllBlocks}</H3>
- * {@link com.oracle.max.graal.compiler.graph#iterateAllBlocks} repeatedly removes a block from the work list and, if not already visited, marks it so,
- * kills the current memory map, sets {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#curBlock}, {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#curState}
- * and {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#lastInstr} and then calls
- * {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#iterateBytecodesForBlock}.
- *
- * This process continues until all the blocks have been visited (processed) after which control returns to {@code
- * build}.
- * <p>
-
- * <H3>{@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#iterateBytecodesForBlock}</H3>
- *
- * {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#iterateBytecodesForBlock} performs an abstract interpretation of the bytecodes in the block, appending new
- * nodes as necessary, until the last added node is an instance of {@link com.oracle.max.graal.compiler.ir.BlockEnd}. (Note: It has an
- * explicit check for finding a new {@link com.oracle.max.graal.compiler.ir.BlockBegin} before a {@link com.oracle.max.graal.compiler.ir.BlockEnd} but
- * {@link com.oracle.max.graal.compiler.graph.BlockMap#moveSuccessorLists} has a similar check so this may be redundant). For example,
- * consider the following bytecodes:
- *
- * <pre>
- * <code>
- *         0: iconst_0
- *         1: istore_2
- *         2: goto 22
- * </code>
- * </pre>
- *
- * The {@code iconst_0} bytecode causes a {@link com.oracle.max.graal.compiler.ir.Constant} node representing zero to be pushed on the
- * {@link com.oracle.max.graal.compiler.phases.GraphBuilderPhase#curState} stack and the node to be appended to the {@link com.oracle.max.graal.compiler.ir.BlockBegin} (entry) node associated with index 0.
- * The {@code istore_2} causes the node to be popped of the stack and stored in the local slot 2. No IR node is
- * generated for the {@code istore_2}. The {@code goto} creates a {@link com.oracle.max.graal.compiler.ir.Goto} node which is a subclass
- * of {@link com.oracle.max.graal.compiler.ir.BlockEnd}, so this terminates the iteration. As part of termination the {@link com.oracle.max.graal.compiler.ir.Goto} node is marked as the
- * end node of the current block and the {@link com.oracle.max.graal.compiler.value.FrameState} is propagated to the successor node(s) by merging any
- * existing {@link com.oracle.max.graal.compiler.value.FrameState} with the current state. If the target is a loop header node this involves inserting
- * {@link com.oracle.max.graal.compiler.ir.Phi} nodes. Finally, the target node is added to the {@code scopeData} work list.
- * <p>
- *
- *
- * @author Ben Titzer
- * @author Mick Jordan
- *
  */
 package com.oracle.max.graal.compiler.graph;