--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/kernel/eka/common/arm/cheap.cia Wed Sep 01 12:34:56 2010 +0100
@@ -0,0 +1,142 @@
+// Copyright (c) 1994-2009 Nokia Corporation and/or its subsidiary(-ies).
+// All rights reserved.
+// This component and the accompanying materials are made available
+// under the terms of the License "Eclipse Public License v1.0"
+// which accompanies this distribution, and is available
+// at the URL "http://www.eclipse.org/legal/epl-v10.html".
+//
+// Initial Contributors:
+// Nokia Corporation - initial contribution.
+//
+// Contributors:
+//
+// Description:
+// e32\common\arm\cheap.cia
+//
+//
+
+#include <e32cia.h>
+#include "../common.h"
+
+#if defined(__HEAP_MACHINE_CODED__) && !defined(_DEBUG)
+GLREF_C void RHeap_PanicBadAllocatedCellSize();
+GLREF_C void RHeap_PanicBadNextCell();
+GLREF_C void RHeap_PanicBadPrevCell();
+GLREF_C void RHeap_PanicBadCellAddress();
+
+IMPORT_D extern const TInt KHeapShrinkHysRatio;
+
+
+__NAKED__ RHeap::SCell* RHeap::DoAlloc(TInt /*aSize*/, SCell*& /*aLastFree*/)
+//
+// Allocate a cell.
+//
+ {
+ asm("stmfd sp!, {r4,r5,lr} ");
+ asm("mov r4, r0 "); // r4=this
+ asm("add r3, r0, #%a0" : : "i" _FOFF(RHeap,iFree)); // r3=pP=&iFree
+ asm("ldr r0, [r3, #4] "); // r0=pC=pP->next
+ asm("cmp r0, #0 ");
+ asm("beq 0f "); // if no free cells, alloc failed
+
+ // optimised unfolded scanning loop
+ asm("2: ");
+ asm("ldmia r0, {r12,r14} "); // r12=pC->size, r14=pC->next
+ asm("cmp r1, r12 "); // compare aSize to size
+ asm("movhi r3, r0 "); // if aSize>size, pP=pC
+ asm("movhis r0, r14 "); // and pC=pC->next
+#ifndef __CPU_ARMV6 // don't unroll on armv6
+ asm("ldmhiia r0, {r12,r14} "); // r12=pC->size, r14=pC->next
+ asm("cmphi r1, r12 "); // compare aSize to size
+ asm("movhi r3, r0 "); // if aSize>size, pP=pC
+ asm("movhis r0, r14 "); // and pC=pC->next
+#endif
+ asm("bhi 2b "); // branch back if scan not finished
+
+ asm("1: ");
+ asm("subs r5, r12, r1 "); // r5 = pC->len - aSize
+ asm("ldrhs r2, [r4, #%a0]" : : "i" _FOFF(RHeap,iMinCell)); // if big enough, r2=iMinCell
+ asm("blo 0f "); // branch if no free cell was big enough
+ asm("cmp r5, r2 "); // leftover big enough?
+ asm("movlo r1, r12 "); // if not, aSize=pC->len ...
+ asm("strlo r14, [r3, #4] "); // ... and pP->next = pC->next
+ asm("addhs r2, r0, r1 "); // else r2 = pE = address of new free cell ...
+ asm("stmhsia r2, {r5, r14} "); // ... pE->len = pC->len - aSize, pE->next = pC->next ...
+ asm("strhs r2, [r3, #4] "); // ... and pP->next = pE
+ asm("str r1, [r0] "); // pC->len = aSize
+ __POPRET("r4,r5,"); // restore and exit, return pC
+
+ asm("0: ");
+ asm("str r3, [r2] "); // alloc failed - aLastFree=pP
+ asm("mov r0, #0 "); // return NULL
+ __POPRET("r4,r5,");
+ }
+
+__NAKED__ void RHeap::DoFree(SCell* /*pC*/)
+//
+// Free a cell.
+//
+ {
+ asm("add r2, r0, #%a0" : : "i" _FOFF(RHeap,iFree)); // r2=pP=&iFree
+ asm("ldr r3, [r2, #4] "); // r3=pE=pP->next
+ asm("stmfd sp!, {r4, r5} ");
+
+ asm("1: ");
+ asm("cmp r3, #0 "); // check if pE=NULL
+ asm("cmphi r1, r3 "); // if not, check if pC>pE
+ asm("movhi r2, r3 "); // if so, pP=pE
+ asm("ldrhi r3, [r3, #4] "); // and pE=pE->next
+#ifndef __CPU_ARMV6 // don't unroll on armv6
+ asm("cmphi r3, #0 "); // check if pE=NULL
+ asm("cmphi r1, r3 "); // if not, check if pC>pE
+ asm("movhi r2, r3 "); // if so, pP=pE
+ asm("ldrhi r3, [r3, #4] "); // and pE=pE->next
+#endif
+ asm("bhi 1b "); // loop if free cell position not found
+
+ asm("ldr r4, [r1, #0] "); // r4=pC->len
+ asm("cmp r3, #0 "); // is there a following free cell ?
+ asm("streq r3, [r1, #4] "); // if not, pC->next=NULL
+ asm("beq 2f "); // and skip next section
+ asm("add r5, r1, r4 "); // r5=pN=pC + pC->len (cell after pC)
+ asm("cmp r5, r3 "); // compare pN with pE
+ asm("ldmeqia r3, {r5, r12} "); // if pN==pE, r5=pE->len, r12=pE->next
+ asm("bhi " CSM_Z22RHeap_PanicBadNextCellv ); // if pN>pE, panic
+ asm("strne r3, [r1, #4] "); // if pN<pE, pC->next=pE
+ asm("addeq r4, r4, r5 "); // if pN==pE r4 = pC->len + pE->len
+ asm("stmeqia r1, {r4,r12} "); // if pN==pE pC->len+=pE->len, pC->next=pE->next
+ asm("2: ");
+ asm("ldr r3, [r2, #0] "); // r3=pP->len
+ asm("sub r5, r1, r2 "); // r5=pC-pP (gap between preceding free cell and this one)
+ asm("cmp r5, r3 "); // compare gap with predecessor length
+ asm("ldreq r12, [r1, #4] "); // if predecessor is adjacent, r12=pC->next
+ asm("blo RHeap_PanicBadPrevCell__Fv "); // if predecessor overlaps, panic
+ asm("addeq r4, r4, r3 "); // if predecessor is adjacent, r4=pC->len + pP->len
+ asm("stmeqia r2, {r4,r12} "); // if predecessor is adjacent, pP->len+=pC->len, pP->next=pC->next
+ asm("strne r1, [r2, #4] "); // else pP->next = pC
+ asm("moveq r1, r2 "); // if predecessor is adjacent, pC=pP (final amalgamated free cell)
+ asm("3: ");
+ asm("ldr r12, [r0, #%a0]" : : "i" _FOFF(RHeap,iTop)); // r12=iTop
+ asm("add r3, r1, r4 "); // end of amalgamated free cell
+ asm("cmp r3, r12 "); // end of amalgamated free cell = iTop ?
+ asm("ldmneia sp!, {r4,r5} "); // restore registers
+ __JUMP(ne,lr); // if not, finished
+ asm("ldr r12, [r0, #%a0]" : : "i" _FOFF(RHeap,iFlags)); // r12=iFlags
+ asm("tst r12, #%a0" : : "i" ((TInt)RAllocator::EFixedSize)); // check fixed size flag
+ asm("ldmneia sp!, {r4,r5} "); // restore registers
+ __JUMP(ne,lr); // if set, finished
+ asm("ldr r2, [r0, #%a0]" : : "i" _FOFF(RHeap,iGrowBy)); // r2=iGrowBy
+ asm("mov r3, r2, LSR #8"); // r3=iGrowBy>>8
+ asm("ldr r2, const_addr"); // r2=&KHeapShrinkHysRatio
+ asm("ldr r5, [r2]"); // r5=KHeapShrinkHysRatio
+ asm("mul r2, r5, r3"); // r2=KHeapShrinkHysRatio*(iGrowBy>>8) - low order bits
+ asm("cmp r4, r2"); // compare len(r4) to (iGrowBy>>8)*KHeapShrinkHysRatio(r2)
+ asm("ldmia sp!, {r4,r5} "); // restore registers
+ __JUMP(lo,lr); // if less, finished
+ asm("b Reduce__5RHeapPQ25RHeap5SCell "); // else reduce heap
+
+ asm("const_addr:");
+ asm(".word %a0" : : "i" ((TInt)&KHeapShrinkHysRatio));
+ }
+#endif
+