1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 /* 17 * Interpreter entry point. 18 */ 19 20 /* 21 * We don't have formal stack frames, so gdb scans upward in the code 22 * to find the start of the function (a label with the %function type), 23 * and then looks at the next few instructions to figure out what 24 * got pushed onto the stack. From this it figures out how to restore 25 * the registers, including PC, for the previous stack frame. If gdb 26 * sees a non-function label, it stops scanning, so either we need to 27 * have nothing but assembler-local labels between the entry point and 28 * the break, or we need to fake it out. 29 * 30 * When this is defined, we add some stuff to make gdb less confused. 31 */ 32 #define ASSIST_DEBUGGER 1 33 34 .text 35 .align 2 36 .global dvmMterpStdRun 37 .type dvmMterpStdRun, %function 38 39 /* 40 * On entry: 41 * r0 Thread* self 42 * 43 * The return comes via a call to dvmMterpStdBail(). 44 */ 45 dvmMterpStdRun: 46 #define MTERP_ENTRY1 \ 47 .save {r4-r10,fp,lr}; \ 48 stmfd sp!, {r4-r10,fp,lr} @ save 9 regs 49 #define MTERP_ENTRY2 \ 50 .pad #4; \ 51 sub sp, sp, #4 @ align 64 52 53 .fnstart 54 MTERP_ENTRY1 55 MTERP_ENTRY2 56 57 /* save stack pointer, add magic word for debuggerd */ 58 str sp, [r0, #offThread_bailPtr] @ save SP for eventual return 59 60 /* set up "named" registers, figure out entry point */ 61 mov rSELF, r0 @ set rSELF 62 LOAD_PC_FP_FROM_SELF() @ load rPC and rFP from "thread" 63 ldr rIBASE, [rSELF, #offThread_curHandlerTable] @ set rIBASE 64 65 #if defined(WITH_JIT) 66 .LentryInstr: 67 /* Entry is always a possible trace start */ 68 ldr r0, [rSELF, #offThread_pJitProfTable] 69 FETCH_INST() 70 mov r1, #0 @ prepare the value for the new state 71 str r1, [rSELF, #offThread_inJitCodeCache] @ back to the interp land 72 cmp r0,#0 @ is profiling disabled? 73 #if !defined(WITH_SELF_VERIFICATION) 74 bne common_updateProfile @ profiling is enabled 75 #else 76 ldr r2, [rSELF, #offThread_shadowSpace] @ to find out the jit exit state 77 beq 1f @ profiling is disabled 78 ldr r3, [r2, #offShadowSpace_jitExitState] @ jit exit state 79 cmp r3, #kSVSTraceSelect @ hot trace following? 80 moveq r2,#kJitTSelectRequestHot @ ask for trace selection 81 beq common_selectTrace @ go build the trace 82 cmp r3, #kSVSNoProfile @ don't profile the next instruction? 83 beq 1f @ intrepret the next instruction 84 b common_updateProfile @ collect profiles 85 #endif 86 1: 87 GET_INST_OPCODE(ip) 88 GOTO_OPCODE(ip) 89 #else 90 /* start executing the instruction at rPC */ 91 FETCH_INST() @ load rINST from rPC 92 GET_INST_OPCODE(ip) @ extract opcode from rINST 93 GOTO_OPCODE(ip) @ jump to next instruction 94 #endif 95 96 .Lbad_arg: 97 ldr r0, strBadEntryPoint 98 @ r1 holds value of entryPoint 99 bl printf 100 bl dvmAbort 101 .fnend 102 .size dvmMterpStdRun, .-dvmMterpStdRun 103 104 105 .global dvmMterpStdBail 106 .type dvmMterpStdBail, %function 107 108 /* 109 * Restore the stack pointer and PC from the save point established on entry. 110 * This is essentially the same as a longjmp, but should be cheaper. The 111 * last instruction causes us to return to whoever called dvmMterpStdRun. 112 * 113 * We pushed some registers on the stack in dvmMterpStdRun, then saved 114 * SP and LR. Here we restore SP, restore the registers, and then restore 115 * LR to PC. 116 * 117 * On entry: 118 * r0 Thread* self 119 */ 120 dvmMterpStdBail: 121 ldr sp, [r0, #offThread_bailPtr] @ sp<- saved SP 122 add sp, sp, #4 @ un-align 64 123 ldmfd sp!, {r4-r10,fp,pc} @ restore 9 regs and return 124 125 126 /* 127 * String references. 128 */ 129 strBadEntryPoint: 130 .word .LstrBadEntryPoint 131
