On Tue, Jul 18, 2017 at 8:07 PM, Christopher Li <sparse@xxxxxxxxxxx> wrote: > ====================== > 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 I see more what is going on there now. Basically we have %phi3 = 1, a constant. There for when control flow go from L0->L1, %r1 = %phi3 = 1. It will go to L4 for sure. So L0 modify to goto L4 directly. That is fine. > > .L1: > phi.32 %r1(ansi) <- VOID, %phi4(ansi) <======= this seems wrong. > cbr %r1(ansi), .L4, .L5 phisrc3 has only one usage on L1. phisrc3 can be optimize away and replace it with value 1. Showing VOID there is wrong. it should be: phi.32 %r1(ansi) <- 1, %phi4(ansi) This phi instruction can't be deleted. Even though the control flow has skip L1 and go to L4 directly. Makes L1 seems unreachable. But the %r1(ansi) inside L1 is still used. I think that is the nature of this bug. Once sparse mistakenly remove %r1(ansi), it goes all crazy. It result in the "setne.32 %r11 <- %r11, $0 " which does not make sense at all. I have revert the change cause this problem on sparse-next. Wine compile should be able to complete now. Luc, do you have time to take a look at this? Without your input, RC5 will be released with commit 11b1a83b disabled. Chris -- To unsubscribe from this list: send the line "unsubscribe linux-sparse" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
