On 11 March 2017 at 22:04, Dibyendu Majumdar <mobile@xxxxxxxxxxxxxxx> wrote:
> I am not sure what is happening here. The test program is:
>
> extern int printf(const char *fmt, ...);
> int main(void) {
> int Count;
> for (Count = 0; Count < 4; Count++)
> {
> printf("%d\n", Count);
> switch (Count)
> {
> case 1:
> printf("%d\n", 1);
> break;
> case 2:
> printf("%d\n", 2);
> break;
> default:
> printf("%d\n", 0);
> break;
> }
> }
> return 0;
> }
>
> The linearized output I get:
>
> main:
> .L0:
> <entry-point>
> phisrc.32 %phi4(Count) <- $0
> br .L4
> .L4:
> phi.32 %r1(Count) <- %phi4(Count), %phi5(Count)
> setlt.32 %r2 <- %r1(Count), $4
> br %r2, .L1, .L9
> .L1:
> symaddr.64 %r3 <- <anon symbol:000001A5682A1E38>
> call.32 %r5 <- printf, %r3, %r1(Count)
> switch %r1(Count), 1 -> .L6, 2 -> .L7, default -> .L8
> .L6:
> symaddr.64 %r7 <- <anon symbol:000001A5682A21B8>
> call.32 %r8 <- printf, %r7, $1
> br .L2
> .L7:
> symaddr.64 %r9 <- <anon symbol:000001A5682A2538>
> call.32 %r10 <- printf, %r9, $2
> br .L2
> .L8:
> symaddr.64 %r11 <- <anon symbol:000001A5682A28B8>
> call.32 %r12 <- printf, %r11, $0
> br .L2
> .L2:
> add.32 %r14 <- %r1(Count), $1
> phisrc.32 %phi5(Count) <- %r14
> br .L4
> .L9:
> ret.32 $0
>
>
> In sparse-llvm the instruction:
> add.32 %r14 <- %r1(Count), $1
>
> fails because the type of %r1(Count) is void. I am not sure why the
> type is void here.
>
Looks like the 'void' is coming from this in output_op_switch() in
sparse-llvm.c:
target = LLVMBuildSwitch(fn->builder, sw_val,
def ? def->priv : NULL, n_jmp);
...
insn->target->priv = target;
So this is probably incorrect. Looks like we should not set
insn->target->priv here as it is already set. Removing the assignment
resolves the issue.
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