On Tue, Jul 18, 2017 at 7:12 PM, Christopher Li <sparse@xxxxxxxxxxx> wrote:
>
> OK, I have shrink the test program into the following code.
> It can still reproduce the dead loop. It is related to simplify
> the phi source.
So I add a show_entry() in side each of the CSE loop.
Here is what I have so far. Commends in <==========
Chris
====================== The original
test_menu_iteminfo:
.L0:
<entry-point>
phisrc.32 %phi3(ansi) <- $1
br .L1
.L1:
phi.32 %r1(ansi) <- %phi3(ansi), %phi4(ansi)
cbr %r1(ansi), .L4, .L5
.L4:
symaddr.64 %r2 <- stringA
cast.64 %r3 <- (64) %r2
br .L5
.L5:
cbr %r1(ansi), .L6, .L7
.L6:
ptrcast.64 %r6 <- (64) %r3
ptrcast.64 %r8 <- (64) VOID
call.64 %r9 <- strcpy, %r6, %r8
br .L7
.L7:
br .L2
.L2:
seteq.32 %r11 <- %r1(ansi), $0
phisrc.32 %phi4(ansi) <- %r11
cbr %r11, .L3, .L1
.L3:
ret
======================
test_menu_iteminfo:
.L0:
<entry-point>
phisrc.32 %phi3(ansi) <- $1
br .L1
.L1:
phi.32 %r1(ansi) <- %phi3(ansi), %phi4(ansi)
cbr %r1(ansi), .L4, .L5
.L4:
### <======= r2 getsymaddr get simplify away
cast.64 %r3 <- (64) stringA
br .L5
.L5:
cbr %r1(ansi), .L6, .L7
.L6:
ptrcast.64 %r6 <- (64) %r3
ptrcast.64 %r8 <- (64) VOID
call.64 %r9 <- strcpy, %r6, %r8
br .L7
.L7:
br .L2
.L2:
seteq.32 %r11 <- %r1(ansi), $0
phisrc.32 %phi4(ansi) <- %r11
cbr %r1(ansi), .L1, .L3
.L3:
ret
======================
test_menu_iteminfo:
.L0:
<entry-point>
phisrc.32 %phi3(ansi) <- $1
br .L1
.L1:
phi.32 %r1(ansi) <- %phi3(ansi), %phi4(ansi)
cbr %r1(ansi), .L4, .L5
.L4:
cast.64 %r3 <- (64) stringA
br .L5
.L5:
cbr %r1(ansi), .L6, .L2
.L6:
ptrcast.64 %r6 <- (64) %r3
ptrcast.64 %r8 <- (64) VOID
call.64 %r9 <- strcpy, %r6, %r8
br .L2 <=============== L2 merge with L7
.L2:
seteq.32 %r11 <- %r1(ansi), $0
phisrc.32 %phi4(ansi) <- %r11
cbr %r1(ansi), .L1, .L3
.L3:
ret
======================
test_menu_iteminfo:
.L0:
<entry-point>
br .L4 <========= phisrc3 get optimize away. This seems wrong
.L1:
phi.32 %r1(ansi) <- VOID, %phi4(ansi) <======= this seems wrong.
cbr %r1(ansi), .L4, .L5
.L4:
cast.64 %r3 <- (64) stringA
br .L5
.L5:
cbr %r1(ansi), .L6, .L3
.L6:
ptrcast.64 %r6 <- (64) %r3
ptrcast.64 %r8 <- (64) VOID
call.64 %r9 <- strcpy, %r6, %r8
br .L2
.L2:
seteq.32 %r11 <- %r1(ansi), $0
phisrc.32 %phi4(ansi) <- %r11
cbr %r1(ansi), .L4, .L3
.L3:
ret
======================
test_menu_iteminfo:
.L0:
<entry-point>
br .L4
.L4:
cast.64 %r3 <- (64) stringA
br .L5
.L5:
cbr %r11, .L3, .L6
.L6:
ptrcast.64 %r6 <- (64) %r3
ptrcast.64 %r8 <- (64) VOID
call.64 %r9 <- strcpy, %r6, %r8
br .L2
.L2:
setne.32 %r11 <- %r11, $0 <====== this seems very wrong
cbr %r11, .L4, .L3
.L3:
ret
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