An array of instructions?

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#1

Another question today: an array of string literals in my C program
was transformed to independent global variables, each holding one
string, and another array of getelementptr's to them, here it is:

@words= global [5 x i8*] [ i8* getelementptr ([10 x i8]* @.str11, i32
0, i32 0), i8* getelementptr ([6 x i8]* @.str12, i32 0, i32 0), i8*
getelementptr ([7 x i8]* @.str13, i32 0, i32 0), i8* getelementptr ([6
x i8]* @.str14, i32 0, i32 0), i8* getelementptr ([11 x i8]* @.str15,
i32 0, i32 0) ] ; <[5 x i8*]*> [#uses=1]

Does this make sense? Are the elements of this array indeed regular
GetElementPtrInst's, which is a kind of Instruction? How can an
instruction live outside of a BasicBlock and a Function?

Thanks,
Harel

#2

Another question today: an array of string literals in my C program
was transformed to independent global variables, each holding one
string, and another array of getelementptr's to them, here it is:

@words= global [5 x i8*] [ i8* getelementptr ([10 x i8]* @.str11, i32
0, i32 0), i8* getelementptr ([6 x i8]* @.str12, i32 0, i32 0), i8*
getelementptr ([7 x i8]* @.str13, i32 0, i32 0), i8* getelementptr ([6
x i8]* @.str14, i32 0, i32 0), i8* getelementptr ([11 x i8]* @.str15,
i32 0, i32 0) ] ; <[5 x i8*]*> [#uses=1]

Does this make sense?

Yes, consider the difference between

const char *const words[2] = { "foo", "bar" };

and

const char words[2][4] = { "foo", "bar" };

The first one is an array of pointers, the second is a two-dimensional array. Your code is a correct translation of the first one.

Are the elements of this array indeed regular
GetElementPtrInst's, which is a kind of Instruction? How can an
instruction live outside of a BasicBlock and a Function?

I am not an LLVM language lawyer, but these GEPs are constant expressions which is allowed, see http://llvm.org/docs/LangRef.html#constantexprs

Regards,
/jakob