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我想了解 dalvik/vm/mterp/armv6t2/wincmp.s 代码：

 %verify "branch taken"
 %verify "branch not taken"
 /*
 * Generic two-operand compare-and-branch operation.  Provide a "revcmp"
 * fragment that specifies the *reverse* comparison to perform, e.g.
 * for "if-le" you would use "gt".
 *
 * For: if-eq, if-ne, if-lt, if-ge, if-gt, if-le
 */
 /* if-cmp vA, vB, +CCCC */
 mov     r1, rINST, lsr #12          @ r1<- B
 ubfx    r0, rINST, #8, #4           @ r0<- A
 GET_VREG(r3, r1)                    @ r3<- vB
 GET_VREG(r2, r0)                    @ r2<- vA
 mov     r9, #4                      @ r0<- BYTE branch dist for not-taken
 cmp     r2, r3                      @ compare (vA, vB)
 b${revcmp}  1f                      @ branch to 1 if comparison failed
 FETCH_S(r9, 1)                      @ r9<- branch offset, in code units
 movs    r9, r9, asl #1              @ convert to bytes, check sign
 bmi     common_backwardBranch       @ yes, do periodic checks
 1:
 #if defined(WITH_JIT)
 GET_JIT_PROF_TABLE(r0)
 FETCH_ADVANCE_INST_RB(r9)           @ update rPC, load rINST
 b        common_testUpdateProfile
 #else
 FETCH_ADVANCE_INST_RB(r9)           @ update rPC, load rINST
 GET_INST_OPCODE(ip)                 @ extract opcode from rINST
 GOTO_OPCODE(ip)                     @ jump to next instruction
 #endif

谁能告诉我第一行 (%verify "branch take") 是什么意思？谢谢你

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1 回答 1

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它本质上只是一个评论。来自 Dalvik mterp 自述文件：

%verify "message"

给自己留个便条，说明需要测试的内容。（这可能有一天会变成更有趣的东西；现在，它只是在生成输出之前被剥离。）

于 2013-05-01T17:08:39.703 回答