* net/loveruby/cflat/compiler/CodeGenerator.java: fix local variables offset after compiling function body, to allow saving really-used callee-saved registers only.

* net/loveruby/cflat/asm/IndirectMemoryReference.java: allow fixing offset out of consructor. * net/loveruby/cflat/asm/AsmStatistics.java: new class. * net/loveruby/cflat/asm/Assembly.java: support #collectStatistics. * net/loveruby/cflat/asm/Instruction.java: ditto. * net/loveruby/cflat/asm/AsmOperand.java: ditto. * net/loveruby/cflat/asm/Register.java: ditto. * net/loveruby/cflat/asm/AbsoluteAddress.java: ditto. * net/loveruby/cflat/asm/DirectMemoryReference.java: ditto. * net/loveruby/cflat/asm/ImmediateValue.java: ditto. * net/loveruby/cflat/ast/Scope.java: refactoring: rename method: #allChildren -> #allScopes. * net/loveruby/cflat/ast/Scope.java (allScopes): should include receiver scope itself. * net/loveruby/cflat/ast/LocalScope.java (allVariables): did not wrongly included current scope's variables. * net/loveruby/cflat/ast/LocalScope.java: refactoring: rename method: allVariables -> allLocalVariables. * net/loveruby/cflat/ast/DefinedFunction.java: ditto. git-svn-id: file:///Users/aamine/c/gitwork/public/cbc/trunk@4040 1b9489fe-b721-0410-924e-b54b9192deb8
2008-09-20 18:04:20 +00:00 · 2008-09-20 18:04:20 +00:00 · 1668b72403
parent 076d0dea13
commit 1668b72403
15 changed files with 304 additions and 71 deletions
--- a/40
+++ b/40
@ -1,3 +1,43 @@
+Sun Sep 21 03:04:16 2008  Minero Aoki  <aamine@loveruby.net>
+
+	* net/loveruby/cflat/compiler/CodeGenerator.java: fix local
+	  variables offset after compiling function body, to allow saving
+	  really-used callee-saved registers only.
+
+	* net/loveruby/cflat/asm/IndirectMemoryReference.java: allow
+	  fixing offset out of consructor.
+
+	* net/loveruby/cflat/asm/AsmStatistics.java: new class.
+
+	* net/loveruby/cflat/asm/Assembly.java: support
+	  #collectStatistics.
+
+	* net/loveruby/cflat/asm/Instruction.java: ditto.
+
+	* net/loveruby/cflat/asm/AsmOperand.java: ditto.
+
+	* net/loveruby/cflat/asm/Register.java: ditto.
+
+	* net/loveruby/cflat/asm/AbsoluteAddress.java: ditto.
+
+	* net/loveruby/cflat/asm/DirectMemoryReference.java: ditto.
+
+	* net/loveruby/cflat/asm/ImmediateValue.java: ditto.
+
+	* net/loveruby/cflat/ast/Scope.java: refactoring: rename method:
+	  #allChildren -> #allScopes.
+
+	* net/loveruby/cflat/ast/Scope.java (allScopes): should include
+	  receiver scope itself.
+
+	* net/loveruby/cflat/ast/LocalScope.java (allVariables): did not
+	  wrongly included current scope's variables.
+
+	* net/loveruby/cflat/ast/LocalScope.java: refactoring: rename
+	  method: allVariables -> allLocalVariables.
+
+	* net/loveruby/cflat/ast/DefinedFunction.java: ditto.
+
 Sat Sep 20 23:48:31 2008  Minero Aoki  <aamine@loveruby.net>

 	* net/loveruby/cflat/compiler/Options.java: new option -O0, -O,
--- a/net/loveruby/cflat/asm/AbsoluteAddress.java
+++ b/net/loveruby/cflat/asm/AbsoluteAddress.java
@ -11,6 +11,10 @@ public class AbsoluteAddress extends AsmOperand {
        return this.register;
    }

+    public void collectStatistics(AsmStatistics stats) {
+        register.collectStatistics(stats);
+    }
+
    public String toSource() {
        return "*" + register.toSource();
    }
--- a/net/loveruby/cflat/asm/AsmOperand.java
+++ b/net/loveruby/cflat/asm/AsmOperand.java
@ -15,6 +15,8 @@ abstract public class AsmOperand implements OperandPattern {
        return null;
    }

+    abstract public void collectStatistics(AsmStatistics stats);
+
    // default implementation
    public boolean match(AsmOperand operand) {
        return equals(operand);
--- a/net/loveruby/cflat/asm/AsmStatistics.java
+++ b/net/loveruby/cflat/asm/AsmStatistics.java
@ -0,0 +1,52 @@
+package net.loveruby.cflat.asm;
+import java.util.*;
+
+public class AsmStatistics {
+    protected Map registerUsage;
+    protected Map insnUsage;
+
+    static public AsmStatistics collect(List assemblies) {
+        AsmStatistics stats = new AsmStatistics();
+        Iterator asms = assemblies.iterator();
+        while (asms.hasNext()) {
+            Assembly asm = (Assembly)asms.next();
+            asm.collectStatistics(stats);
+        }
+        return stats;
+    }
+
+    public AsmStatistics() {
+        registerUsage = new HashMap();
+        insnUsage = new HashMap();
+    }
+
+    public int numRegisterUsage(String name) {
+        return fetchCount(registerUsage, name);
+    }
+
+    public void registerUsed(String name) {
+        incrementCount(registerUsage, name);
+    }
+
+    public int numInstructionUsage(String insn) {
+        return fetchCount(insnUsage, insn);
+    }
+
+    public void instructionUsed(String insn) {
+        incrementCount(insnUsage, insn);
+    }
+
+    protected int fetchCount(Map m, String name) {
+        Integer n = (Integer)m.get(name);
+        if (n == null) {
+            return 0;
+        }
+        else {
+            return n.intValue();
+        }
+    }
+
+    protected void incrementCount(Map m, String name) {
+        m.put(name, new Integer(fetchCount(m, name) + 1));
+    }
+}
--- a/net/loveruby/cflat/asm/Assembly.java
+++ b/net/loveruby/cflat/asm/Assembly.java
@ -10,4 +10,8 @@ abstract public class Assembly {
    public boolean isLabel() {
        return false;
    }
+
+    public void collectStatistics(AsmStatistics stats) {
+        // does nothing by default.
+    }
 }
--- a/net/loveruby/cflat/asm/DirectMemoryReference.java
+++ b/net/loveruby/cflat/asm/DirectMemoryReference.java
@ -15,6 +15,10 @@ public class DirectMemoryReference extends MemoryReference {
        return this.value;
    }

+    public void collectStatistics(AsmStatistics stats) {
+        // does nothing
+    }
+
    public String toSource() {
        return this.value.toSource();
    }
--- a/net/loveruby/cflat/asm/ImmediateValue.java
+++ b/net/loveruby/cflat/asm/ImmediateValue.java
@ -21,6 +21,10 @@ public class ImmediateValue extends AsmOperand {
        return this.expr;
    }

+    public void collectStatistics(AsmStatistics stats) {
+        // does nothing
+    }
+
    public String toSource() {
        return "$" + expr.toSource();
    }
--- a/net/loveruby/cflat/asm/IndirectMemoryReference.java
+++ b/net/loveruby/cflat/asm/IndirectMemoryReference.java
@ -3,25 +3,44 @@ package net.loveruby.cflat.asm;
 public class IndirectMemoryReference extends MemoryReference {
    protected long offset;
    protected Register base;
+    protected boolean fixed;

    public IndirectMemoryReference(Register base) {
-        this(0, base);
+        this.offset = 0;
+        this.base = base;
+        this.fixed = false;
    }

    public IndirectMemoryReference(long offset, Register base) {
        this.offset = offset;
        this.base = base;
+        this.fixed = true;
    }

    public long offset() {
        return offset;
    }

+    public void fixOffset(long realOffset) {
+        if (fixed) {
+            throw new Error("must not happen: fixed = true");
+        }
+        this.offset = realOffset;
+        this.fixed = true;
+    }
+
    public Register base() {
        return base;
    }

+    public void collectStatistics(AsmStatistics stats) {
+        base.collectStatistics(stats);
+    }
+
    public String toSource() {
+        if (! fixed) {
+            throw new Error("must not happen: writing unfixed variable");
+        }
        return (offset == 0 ? "" : "" + offset) + "(" + base.toSource() + ")";
    }
 }
--- a/net/loveruby/cflat/asm/Instruction.java
+++ b/net/loveruby/cflat/asm/Instruction.java
@ -53,6 +53,13 @@ public class Instruction extends Assembly {
        return this.operands[1];
    }

+    public void collectStatistics(AsmStatistics stats) {
+        stats.instructionUsed(mnemonic);
+        for (int i = 0; i < operands.length; i++) {
+            operands[i].collectStatistics(stats);
+        }
+    }
+
    public String toSource() {
        StringBuffer buf = new StringBuffer();
        buf.append("\t");
--- a/net/loveruby/cflat/asm/Register.java
+++ b/net/loveruby/cflat/asm/Register.java
@ -61,6 +61,10 @@ public class Register extends AsmOperand {
        return false;
    }

+    public void collectStatistics(AsmStatistics stats) {
+        stats.registerUsed(name);
+    }
+
    public String toSource() {
        return "%" + name();
    }
--- a/net/loveruby/cflat/ast/DefinedFunction.java
+++ b/net/loveruby/cflat/ast/DefinedFunction.java
@ -44,7 +44,7 @@ public class DefinedFunction extends Function {
     * Does NOT include static local variables.
     */
    public Iterator localVariables() {
-        return scope.allVariables();
+        return scope.allLocalVariables();
    }

    class JumpEntry {
--- a/net/loveruby/cflat/ast/DefinedVariable.java
+++ b/net/loveruby/cflat/ast/DefinedVariable.java
@ -38,8 +38,9 @@ public class DefinedVariable extends Variable {
    }

    public MemoryReference memref() {
-        if (memref == null)
+        if (memref == null) {
            throw new Error("unresolved variable address");
+        }
        return memref;
    }

--- a/net/loveruby/cflat/ast/LocalScope.java
+++ b/net/loveruby/cflat/ast/LocalScope.java
@ -19,14 +19,21 @@ public class LocalScope extends Scope {
        return children.iterator();
    }

-    // Returns local variables defined in this scope.
-    // Does includes all nested local variables.
-    // Does NOT include static local variables.
+    /**
+     * Returns local variables defined in this scope.
+     * Does NOT includes children's local variables.
+     * Does NOT include static local variables.
+     */
    public Iterator variables() {
-        return variablesList().iterator();
+        return lvarList().iterator();
    }

-    protected List variablesList() {
+    /**
+     * Returns local variables defined in this scope.
+     * Does NOT includes children's local variables.
+     * Does NOT include static local variables.
+     */
+    protected List lvarList() {
        List result = new ArrayList();
        Iterator ents = entities.values().iterator();
        while (ents.hasNext()) {
@ -41,9 +48,13 @@ public class LocalScope extends Scope {
        return result;
    }

+    /**
+     * Returns the number of all entities in this scope.
+     * Result includes the number of children's entities.
+     */
    public long numAllEntities() {
        if (numAllEntities < 0) {
-            Iterator cs = allChildren();
+            Iterator cs = allScopes().iterator();
            long n = 0;
            while (cs.hasNext()) {
                Scope c = (Scope)cs.next();
@ -54,26 +65,32 @@ public class LocalScope extends Scope {
        return numAllEntities;
    }

-    // Returns all function local variables defined in this scope.
-    // Does includes all nested local variables.
-    // Does NOT include static local variables.
-    public Iterator allVariables() {
-        return allEntities().iterator();
+    /**
+     * Returns all local variables in this scope.
+     * The result DOES includes all nested local variables,
+     * while it does NOT include static local variables.
+     */
+    public Iterator allLocalVariables() {
+        return allLocalVariablesList().iterator();
    }

-    protected List allEntities() {
+    // List<DefinedVariable>
+    protected List allLocalVariablesList() {
        List result = new ArrayList();
-        Iterator scopes = allChildren();
+        Iterator scopes = allScopes().iterator();
        while (scopes.hasNext()) {
            LocalScope s = (LocalScope)scopes.next();
-            result.addAll(s.variablesList());
+            result.addAll(s.lvarList());
        }
        return result;
    }

+    /**
+     * Returns all static local variables defined in this scope.
+     */
    public List staticLocalVariables() {
        List result = new ArrayList();
-        Iterator scopes = allChildren();
+        Iterator scopes = allScopes().iterator();
        while (scopes.hasNext()) {
            LocalScope s = (LocalScope)scopes.next();
            Iterator vars = s.entities.values().iterator();
--- a/net/loveruby/cflat/ast/Scope.java
+++ b/net/loveruby/cflat/ast/Scope.java
@ -37,20 +37,19 @@ abstract public class Scope {
        children.add(s);
    }

-    // Returns a list of all child scopes.
-    // Does NOT include myself.
-    protected Iterator allChildren() {
+    // Returns a list of all child scopes including this scope.
+    protected List allScopes() {
        List result = new ArrayList();
-        collectChildren(result);
-        return result.iterator();
+        collectScope(result);
+        return result;
    }

-    protected void collectChildren(List buf) {
+    protected void collectScope(List buf) {
+        buf.add(this);
        Iterator cs = children.iterator();
        while (cs.hasNext()) {
            Scope c = (Scope)cs.next();
-            buf.add(c);
-            c.collectChildren(buf);
+            c.collectScope(buf);
        }
    }

--- a/net/loveruby/cflat/compiler/CodeGenerator.java
+++ b/net/loveruby/cflat/compiler/CodeGenerator.java
@ -187,28 +187,35 @@ public class CodeGenerator extends Visitor implements ASTLHSVisitor {
    protected void compileFunction(DefinedFunction func) {
        long numSavedRegs = 0;  // 1 for PIC
        allocateParameters(func);
-        long lvarBytes = allocateLocalVariables(func, numSavedRegs);
+        allocateLocalVariablesTemp(func.body().scope());
+
+        List bodyAsms = compileFunctionBody(func);
+        AsmStatistics stats = AsmStatistics.collect(bodyAsms);
+        List usedCalleeSavedRegs = usedCalleeSavedRegs(stats);
+        long lvarBytes = allocateLocalVariables(func.body().scope(),
+                                                usedCalleeSavedRegs.size());

-        currentFunction = func;
        String symbol = csymbol(func.name());
        if (! func.isPrivate()) {
            _globl(symbol);
        }
        _type(symbol, "@function");
        label(symbol);
-        prologue(func, lvarBytes);
-        compileFunctionBody(func.body());
-        epilogue(func, lvarBytes);
+        prologue(func, usedCalleeSavedRegs, lvarBytes);
+        as.addAll(bodyAsms);
+        epilogue(func, usedCalleeSavedRegs, lvarBytes);
        _size(symbol, ".-" + symbol);
    }
    // #@@}

-    protected void compileFunctionBody(Node body) {
+    protected List compileFunctionBody(DefinedFunction func) {
+        currentFunction = func;
        this.as = newAssembler();
-        compile(body);
+        compile(func.body());
        List assemblies = this.as.assemblies();
        this.as = this.assembler;
-        this.as.addAll(optimizer.optimize(assemblies));
+        currentFunction = null;
+        return optimizer.optimize(assemblies);
    }

    // #@@range/compile{
@ -231,47 +238,45 @@ public class CodeGenerator extends Visitor implements ASTLHSVisitor {
    }
    // #@@}

-    // #@@range/prologue{
-    protected void prologue(DefinedFunction func, long lvarBytes) {
-        push(bp());
-        mov(sp(), bp());
-        extendStack(lvarBytes);
+    protected List usedCalleeSavedRegs(AsmStatistics stats) {
+        List result = new ArrayList();
+        Iterator regs = calleeSavedRegisters().iterator();
+        while (regs.hasNext()) {
+            Register reg = (Register)regs.next();
+            if (stats.numRegisterUsage(reg.baseName()) > 0) {
+                result.add(reg);
+            }
+        }
+        return result;
    }
-    // #@@}

-    // #@@range/epilogue{
-    protected void epilogue(DefinedFunction func, long lvarBytes) {
-        label(epilogueLabel(func));
-        shrinkStack(lvarBytes);
-        mov(bp(), sp());
-        pop(bp());
-        ret();
-    }
-    // #@@}
+    protected List calleeSavedRegistersCache = null;

-    // #@@range/jmpEpilogue{
-    protected void jmpEpilogue() {
-        jmp(new Label(epilogueLabel(currentFunction)));
+    protected List calleeSavedRegisters() {
+        if (calleeSavedRegistersCache == null) {
+            ArrayList regs = new ArrayList();
+            regs.add(reg("bx"));
+            regs.add(reg("si"));
+            regs.add(reg("di"));
+            regs.add(reg("bp"));
+            calleeSavedRegistersCache = regs;
+        }
+        return calleeSavedRegistersCache;
    }
-    // #@@}
-
-    // #@@range/epilogueLabel{
-    protected String epilogueLabel(DefinedFunction func) {
-        return ".L" + func.name() + "$epilogue";
-    }
-    // #@@}

    /* Standard IA-32 stack frame layout (after prologue)
     *
     * ======================= esp (stack top)
     * temporary
     * variables...
-     * ---------------------   ebp-(4*3)
+     * ---------------------   ebp-(4*4)
     * lvar 3
-     * ---------------------   ebp-(4*2)
+     * ---------------------   ebp-(4*3)
     * lvar 2
-     * ---------------------   ebp-(4*1)
+     * ---------------------   ebp-(4*2)
     * lvar 1
+     * ---------------------   ebp-(4*1)
+     * callee-saved register
     * ======================= ebp
     * saved ebp
     * ---------------------   ebp+(4*1)
@ -296,6 +301,59 @@ public class CodeGenerator extends Visitor implements ASTLHSVisitor {
    // +1 for return address, +1 for saved bp
    static final protected long paramStartWord = 2;

+    // #@@range/prologue{
+    protected void prologue(DefinedFunction func,
+                            List saveRegs, long lvarBytes) {
+        push(bp());
+        mov(sp(), bp());
+        Iterator regs = saveRegs.iterator();
+        while (regs.hasNext()) {
+            Register reg = (Register)regs.next();
+            // bp is already saved
+            if (! reg.baseName().equals("bp")) {
+                push(reg);
+            }
+        }
+        extendStack(lvarBytes);
+
+        Iterator vars = func.localVariables();
+        while (vars.hasNext()) {
+            DefinedVariable var = (DefinedVariable)vars.next();
+            comment("mem " + var.memref().toSource() + ": " + var.name());
+        }
+    }
+    // #@@}
+
+    // #@@range/epilogue{
+    protected void epilogue(DefinedFunction func,
+                            List savedRegs, long lvarBytes) {
+        label(epilogueLabel(func));
+        shrinkStack(lvarBytes);
+        Iterator regs = savedRegs.iterator();
+        while (regs.hasNext()) {
+            Register reg = (Register)regs.next();
+            if (! reg.baseName().equals("bp")) {
+                pop(reg);
+            }
+        }
+        mov(bp(), sp());
+        pop(bp());
+        ret();
+    }
+    // #@@}
+
+    // #@@range/jmpEpilogue{
+    protected void jmpEpilogue() {
+        jmp(new Label(epilogueLabel(currentFunction)));
+    }
+    // #@@}
+
+    // #@@range/epilogueLabel{
+    protected String epilogueLabel(DefinedFunction func) {
+        return ".L" + func.name() + "$epilogue";
+    }
+    // #@@}
+
    protected void allocateParameters(DefinedFunction func) {
        Iterator vars = func.parameters();
        long word = paramStartWord;
@ -311,12 +369,26 @@ public class CodeGenerator extends Visitor implements ASTLHSVisitor {
        }
    }

-    // Fixes addresses of local variables.
-    // Returns byte-length of the local variable area.
-    protected long allocateLocalVariables(DefinedFunction func,
-                                          long numSavedRegs) {
-        long initLen = numSavedRegs * stackWordSize;
-        long maxLen = allocateScope(func.body().scope(), initLen);
+    /**
+     * Allocates addresses of local variables, but offset is still
+     * not determined, assign unfixed IndirectMemoryReference.
+     */
+    protected void allocateLocalVariablesTemp(LocalScope scope) {
+        Iterator vars = scope.allLocalVariables();
+        while (vars.hasNext()) {
+            DefinedVariable var = (DefinedVariable)vars.next();
+            var.setMemref(new IndirectMemoryReference(bp()));
+        }
+    }
+
+    /**
+     * Fixes addresses of local variables.
+     * Returns byte-length of the local variable area.
+     * Note that numSavedRegs includes bp.
+     */
+    protected long allocateLocalVariables(LocalScope scope, long numSavedRegs) {
+        long initLen = (numSavedRegs - 1) * stackWordSize;
+        long maxLen = allocateScope(scope, initLen);
        return maxLen - initLen;
    }

@ -327,10 +399,10 @@ public class CodeGenerator extends Visitor implements ASTLHSVisitor {
            DefinedVariable var = (DefinedVariable)vars.next();
            if (stackGrowsLower) {
                len = Assembler.align(len + var.allocSize(), stackAlignment);
-                var.setMemref(mem(-len, bp()));
+                fixMemref((IndirectMemoryReference)var.memref(), -len);
            }
            else {
-                var.setMemref(mem(len, bp()));
+                fixMemref((IndirectMemoryReference)var.memref(), len);
                len = Assembler.align(len + var.allocSize(), stackAlignment);
            }
        }
@ -346,6 +418,10 @@ public class CodeGenerator extends Visitor implements ASTLHSVisitor {
        return maxLen;
    }

+    protected void fixMemref(IndirectMemoryReference memref, long offset) {
+        memref.fixOffset(offset);
+    }
+
    protected void extendStack(long len) {
        if (len > 0) {
            add(imm(len * (stackGrowsLower ? -1 : 1)), sp());
@ -886,7 +962,7 @@ public class CodeGenerator extends Visitor implements ASTLHSVisitor {
    }

    protected IndirectMemoryReference mem(Register reg) {
-        return new IndirectMemoryReference(reg);
+        return new IndirectMemoryReference(0, reg);
    }

    protected IndirectMemoryReference mem(long offset, Register reg) {