> +//
> ===-------------------------------------------------------------------
> --===//
> +
> +We compiles the following using a jump table.
This is the target-independent "shift trick", which applies any time
you have a small number of unique destinations, and a spread smaller
than your GPR size.
-Chris
> +define i16 @func_entry_2E_ce(i32 %i) {
> +newFuncRoot:
> + br label %entry.ce
> +
> +bb12.exitStub: ; preds = %entry.ce
> + ret i16 0
> +
> +bb4.exitStub: ; preds = %entry.ce, %entry.ce, %entry.ce
> + ret i16 1
> +
> +bb9.exitStub: ; preds = %entry.ce, %entry.ce, %entry.ce
> + ret i16 2
> +
> +bb.exitStub: ; preds = %entry.ce
> + ret i16 3
> +
> +entry.ce: ; preds = %newFuncRoot
> + switch i32 %i, label %bb12.exitStub [
> + i32 0, label %bb4.exitStub
> + i32 1, label %bb9.exitStub
> + i32 2, label %bb4.exitStub
> + i32 3, label %bb4.exitStub
> + i32 7, label %bb9.exitStub
> + i32 8, label %bb.exitStub
> + i32 9, label %bb9.exitStub
> + ]
> +}
> +
> +gcc compiles to:
> +
> + cmp r0, #9
> + @ lr needed for prologue
> + bhi L2
> + ldr r3, L11
> + mov r2, #1
> + mov r1, r2, asl r0
> + ands r0, r3, r2, asl r0
> + movne r0, #2
> + bxne lr
> + tst r1, #13
> + beq L9
> +L3:
> + mov r0, r2
> + bx lr
> +L9:
> + tst r1, #256
> + movne r0, #3
> + bxne lr
> +L2:
> + mov r0, #0
> + bx lr
> +L12:
> + .align 2
> +L11:
> + .long 642
>
>
>
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