In the following examples ret is referred to as uninferable, this is only true if implicit-return mode is off
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Call to debug_printf(), from 80001a84, in main():
00000000800019e8 <main>: ........: ... 80001a80: f6d42423 {sw a3,-152(s0)} 80001a84: ef4ff0ef {jal x1,80001178} <debug_printf>PC: 80001a84 →80001178
The target of the jal is inferable, thus NO te_inst packet is sent.0000000080001178 <debug_printf>: 80001178: 7139 {addi sp,sp,-64} 8000117a: ... -
Return from debug_printf():
80001186: ... 80001188: 6121 {addi sp,sp,64} 8000118a: 8082 {ret}PC: 8000118a →80001a88
The target of the ret is uninferable, thus a te_inst packet IS sent: te_inst[format=2 (ADDR_ONLY): address=0x80001a88, updiscon=0]80001a88: 00000597 {auipc a1,0x0}} 80001a8c: 65058593 {addi a1,a1,1616}} # 800020d8 <main+0x6f0> -
exiting from Func_2(), with a final taken branch, followed by a ret
00000000800010b6 <Func_2>: ........: .... 800010da: 4781 {li a5,0} 800010dc: 00a05863 {blez a0,800010ec} <Func_2+0x36>PC: 800010dc →800010ec, add branch TAKEN to branch_map, but no packet sent yet.
branches = 0; branch_map = 0;
branch_map = 0 <<branches++;800010ec: 60e2 {ld ra,24(sp)} 800010ee: 6442 {ld s0,16(sp)} 800010f0: 64a2 {ld s1,8(sp)} 800010f2: 853e {mv a0,a5} 800010f4: 6105 {addi sp,sp,32} 800010f6: 8082 {ret}PC: 800010f6 →80001b8a
The target of the ret is uninferable, thus a te_inst packet is sent, with ONE branch in the branch_map
te_inst[ format=1 (DIFF_DELTA): branches=1, branch_map=0x0, address=0x80001b8a (\(\Delta\)=0xab0) updiscon=0 ]00000000800019e8 <main>: ........: .... 80001b8a: f4442603 {lw a2,-188(s0)} 80001b8e: .... -
3 branches, then a function return back to Proc_1()
0000000080001100 <Proc_6>: ........: .... 80001112: c080 {sw s0,0(s1)} 80001114: 4785 {li a5,1} 80001116: 02f40463 {beq s0,a5,8000113e <Proc_6+0x3e>}PC: 80001116 →8000111a, add branch NOT taken to branch_map, but no packet sent yet. branches = 0; branch_map = 0; branch_map = 1 <<branches++;
8000111a: c81d {beqz s0,80001150 <Proc_6+0x50>}PC: 8000111a →8000111c, add branch NOT taken to branch_map, but no packet sent yet.
branch_map = 1 <<branches++;8000111c: 4709 {li a4,2} 8000111e: 04e40063 {beq s0,a4,8000115e <Proc_6+0x5e>}PC: 8000111e →8000115e, add branch TAKEN to branch_map, but no packet sent yet.
branch_map = 0 <<branches++;8000115e: 60e2 {ld ra,24(sp)} 80001160: 6442 {ld s0,16(sp)} 80001162: c09c {sw a5,0(s1)} 80001164: 64a2 {ld s1,8(sp)} 80001166: 6105 {addi sp,sp,32} 80001168: 8082 {ret}00000000800011d6 <Proc\_1>: ........: .... 80001258: 00093783 {ld a5,0(s2)} 8000125c: ....PC: 80001168 →80001258
The target of the ret is uninferable, thus a te_inst packet is sent, with THREE branches in the branch_map
te_inst[ format=1 (DIFF_DELTA): branches=3, branch_map=0x3, address=0x80001258 (\(\Delta\)=0x148), updiscon=0 ] -
A complex example with 2 branches, 2 jal, and a ret
00000000800011d6 <Proc\_1>: ........: .... 8000121c: 441c {lw a5,8(s0)} 8000121e: c795 {beqz a5,8000124a} <Proc_1+0x74>PC: 8000121e →8000124a, add branch TAKEN to branch_map, but no packet sent yet.
branches = 0; branch_map = 0;
branch_map = 0 <<branches++;8000124a: 44c8 {lw a0,12(s1)} 8000124c: 4799 {li a5,6} 8000124e: 00c40593 {addi a1,s0,12} 80001252: c81c {sw a5,16(s0)} 80001254: eadff0ef {jal x1,80001100} <Proc_6>PC: 80001254 →80001100
The target of the jal is inferable, thus no te_inst packet needs be sent.0000000080001100 <Proc_6>: 80001100: 1101 {addi sp,sp,-32} 80001102: e822 {sd s0,16(sp)} 80001104: e426 {sd s1,8(sp)} 80001106: ec06 {sd ra,24(sp)} 80001108: 842a {mv s0,a0} 8000110a: 84ae {mv s1,a1} 8000110c: fedff0ef {jal x1,800010f8} <Func_3>PC: 8000110c →800010f8
The target of the jal is inferable, thus no te_inst packet needs to be sent.00000000800010f8 <Func_3>: 800010f8: 1579 {addi a0,a0,-2} 800010fa: 00153513 {seqz a0,a0} 800010fe: 8082 {ret}PC: 800010fe →80001110
The target of the ret is uninferable, thus a te_inst packet will be sent shortly.0000000080001100 <Proc_6>: ........: .... 80001110: c115 {beqz a0,80001134} <Proc_6+0x34> 80001112: ....PC: 80001110 →80001112, add branch NOT TAKEN to branch_map.
branch_map = 1 <<branches++;
te_inst[ format=1 (DIFF_DELTA): branches=2, branch_map=0x2, address=0x80001110 (\(\Delta\)=0xfffffffffffffef4), updiscon=1 ]