lli won't take kindly to rust's LLVM IR - llvm
I have the following rust code.
$ cat hello.rs
fn main() {
println!("Hello world!");
}
$ rustc hello.rs; ./hello
Hello world!
And I'm producing llvm byte code with the --emit=ir option.
$ rustc --emit=ir hello.rs
$ cat hello.ll
; ModuleID = 'hello.rs'
target datalayout = "e-i64:64-f80:128-n8:16:32:64"
target triple = "x86_64-apple-darwin"
%str_slice = type { i8*, i64 }
%"struct.core::fmt::Argument<[]>[#3]" = type { %"enum.core::result::Result<[(), core::fmt::FormatError]>[#3]" (%"enum.core::fmt::Void<[]>[#3]"*, %"struct.core::fmt::Formatter<[]>[#3]"*)*, %"enum.core::fmt::Void<[]>[#3]"* }
%"enum.core::result::Result<[(), core::fmt::FormatError]>[#3]" = type { i8, [0 x i8], [1 x i8] }
%"struct.core::fmt::Formatter<[]>[#3]" = type { i64, i32, i8, %"enum.core::option::Option<[uint]>[#3]", %"enum.core::option::Option<[uint]>[#3]", { void (i8*)**, i8* }, %"struct.core::slice::Items<[core::fmt::Argument]>[#3]", { %"struct.core::fmt::Argument<[]>[#3]"*, i64 } }
%"enum.core::option::Option<[uint]>[#3]" = type { i8, [7 x i8], [1 x i64] }
%"struct.core::slice::Items<[core::fmt::Argument]>[#3]" = type { %"struct.core::fmt::Argument<[]>[#3]"*, %"struct.core::fmt::Argument<[]>[#3]"*, %"struct.core::kinds::marker::ContravariantLifetime<[]>[#3]" }
%"struct.core::kinds::marker::ContravariantLifetime<[]>[#3]" = type {}
%"enum.core::fmt::Void<[]>[#3]" = type {}
%"struct.core::fmt::Arguments<[]>[#3]" = type { { %"enum.core::fmt::rt::Piece<[]>[#3]"*, i64 }, { %"struct.core::fmt::Argument<[]>[#3]"*, i64 } }
%"enum.core::fmt::rt::Piece<[]>[#3]" = type { i8, [7 x i8], [8 x i64] }
#str1364 = internal constant [12 x i8] c"Hello world!"
#_ZN4main15__STATIC_FMTSTR20h3b67a4ad8efbb398oaaE = internal unnamed_addr constant { { i8, %str_slice, [48 x i8] } } { { i8, %str_slice, [48 x i8] } { i8 0, %str_slice { i8* getelementptr inbounds ([12 x i8]* #str1364, i32 0, i32 0), i64 12 }, [48 x i8] undef } }
; Function Attrs: uwtable
define internal void #_ZN4main20he3565cca0bc2f101eaaE() unnamed_addr #0 {
entry-block:
%match = alloca {}
%__args_vec = alloca { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }
%0 = alloca %"struct.core::fmt::Argument<[]>[#3]", i64 0
%__args = alloca %"struct.core::fmt::Arguments<[]>[#3]"
%__adjust = alloca { %"enum.core::fmt::rt::Piece<[]>[#3]"*, i64 }
%__adjust1 = alloca { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }
br label %case_body
case_body: ; preds = %entry-block
%1 = getelementptr inbounds { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }* %__args_vec, i32 0, i32 0
store %"struct.core::fmt::Argument<[]>[#3]"* %0, %"struct.core::fmt::Argument<[]>[#3]"** %1
%2 = getelementptr inbounds { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }* %__args_vec, i32 0, i32 1
store i64 0, i64* %2
%3 = getelementptr inbounds { %"enum.core::fmt::rt::Piece<[]>[#3]"*, i64 }* %__adjust, i32 0, i32 0
store %"enum.core::fmt::rt::Piece<[]>[#3]"* getelementptr inbounds ([1 x %"enum.core::fmt::rt::Piece<[]>[#3]"]* bitcast ({ { i8, %str_slice, [48 x i8] } }* #_ZN4main15__STATIC_FMTSTR20h3b67a4ad8efbb398oaaE to [1 x %"enum.core::fmt::rt::Piece<[]>[#3]"]*), i32 0, i32 0), %"enum.core::fmt::rt::Piece<[]>[#3]"** %3
%4 = getelementptr inbounds { %"enum.core::fmt::rt::Piece<[]>[#3]"*, i64 }* %__adjust, i32 0, i32 1
store i64 1, i64* %4
%5 = getelementptr inbounds { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }* %__args_vec, i32 0, i32 0
%6 = load %"struct.core::fmt::Argument<[]>[#3]"** %5
%7 = getelementptr inbounds { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }* %__args_vec, i32 0, i32 1
%8 = load i64* %7
%9 = getelementptr inbounds { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }* %__adjust1, i32 0, i32 0
store %"struct.core::fmt::Argument<[]>[#3]"* %6, %"struct.core::fmt::Argument<[]>[#3]"** %9
%10 = getelementptr inbounds { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }* %__adjust1, i32 0, i32 1
store i64 %8, i64* %10
call void #"_ZN3fmt22Arguments$LT$$x27a$GT$3new20h30af698883d0f4c86aaE"(%"struct.core::fmt::Arguments<[]>[#3]"* noalias nocapture sret dereferenceable(32) %__args, { %"enum.core::fmt::rt::Piece<[]>[#3]"*, i64 }* noalias nocapture dereferenceable(16) %__adjust, { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }* noalias nocapture dereferenceable(16) %__adjust1)
call void #_ZN2io5stdio12println_args20hecac3fc58fb73442EvmE(%"struct.core::fmt::Arguments<[]>[#3]"* noalias nocapture dereferenceable(32) %__args)
br label %join
join: ; preds = %case_body
ret void
}
define i64 #main(i64, i8**) unnamed_addr #1 {
top:
%2 = call i64 #_ZN10lang_start20h7823875e69d425d0BueE(i8* bitcast (void ()* #_ZN4main20he3565cca0bc2f101eaaE to i8*), i64 %0, i8** %1)
ret i64 %2
}
declare i64 #_ZN10lang_start20h7823875e69d425d0BueE(i8*, i64, i8**) unnamed_addr #1
; Function Attrs: inlinehint uwtable
define internal void #"_ZN3fmt22Arguments$LT$$x27a$GT$3new20h30af698883d0f4c86aaE"(%"struct.core::fmt::Arguments<[]>[#3]"* noalias nocapture sret dereferenceable(32), { %"enum.core::fmt::rt::Piece<[]>[#3]"*, i64 }* noalias nocapture dereferenceable(16), { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }* noalias nocapture dereferenceable(16)) unnamed_addr #2 {
entry-block:
%__adjust = alloca { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }
%3 = getelementptr inbounds %"struct.core::fmt::Arguments<[]>[#3]"* %0, i32 0, i32 0
%4 = bitcast { %"enum.core::fmt::rt::Piece<[]>[#3]"*, i64 }* %1 to i8*
%5 = bitcast { %"enum.core::fmt::rt::Piece<[]>[#3]"*, i64 }* %3 to i8*
call void #llvm.memcpy.p0i8.p0i8.i64(i8* %5, i8* %4, i64 16, i32 8, i1 false)
%6 = getelementptr inbounds %"struct.core::fmt::Arguments<[]>[#3]"* %0, i32 0, i32 1
%7 = getelementptr inbounds { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }* %2, i32 0, i32 0
%8 = load %"struct.core::fmt::Argument<[]>[#3]"** %7
%9 = getelementptr inbounds { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }* %2, i32 0, i32 1
%10 = load i64* %9
%11 = getelementptr inbounds { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }* %__adjust, i32 0, i32 0
store %"struct.core::fmt::Argument<[]>[#3]"* %8, %"struct.core::fmt::Argument<[]>[#3]"** %11
%12 = getelementptr inbounds { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }* %__adjust, i32 0, i32 1
store i64 %10, i64* %12
%13 = bitcast { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }* %__adjust to i8*
%14 = bitcast { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }* %6 to i8*
call void #llvm.memcpy.p0i8.p0i8.i64(i8* %14, i8* %13, i64 16, i32 8, i1 false)
ret void
}
; Function Attrs: nounwind
declare void #llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture readonly, i64, i32, i1) unnamed_addr #3
declare void #_ZN2io5stdio12println_args20hecac3fc58fb73442EvmE(%"struct.core::fmt::Arguments<[]>[#3]"* noalias nocapture dereferenceable(32)) unnamed_addr #1
attributes #0 = { uwtable "split-stack" }
attributes #1 = { "split-stack" }
attributes #2 = { inlinehint uwtable "split-stack" }
attributes #3 = { nounwind "split-stack" }
However, lli won't accept this bytecode.
$ lli hello.ll
lli: hello.ll:47:138: error: expected value token
call void #"_ZN3fmt22Arguments$LT$$x27a$GT$3new20h30af698883d0f4c86aaE"(%"struct.core::fmt::Arguments<[]>[#3]"* noalias nocapture sret dereferenceable(32) %__args, { %"enum.core::fmt::rt::Piece<[]>[#3]"*, i64 }* noalias nocapture dereferenceable(16) %__adjust, { %"struct.core::fmt::Argument<[]>[#3]"*, i64 }* noalias nocapture dereferenceable(16) %__adjust1)
^
Any ideas why?
The dereferenceable attribute was added to LLVM just last month (July 2014). I'm assuming the rustc you are using is based on brand new LLVM code while your lli is slightly older. To fix this, update your code and rebuild.
The dereferenceable attribute was added in a commit one month before the OP, so if you are using a released LLVM package, you may not be using a recent enough package.
Try using an LLVM package built from top of trunk.
Related
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The return value of getOperand function is Value* object of the argc variable (variable newOperand in your code). You can pass that value to any new instruction that you might want to inject (for example CreateICmpEQ) in the IR to compare value of argc with some constant value.
LLVM Create VarArg Function and access var args
I have been trying to create a function using the module pass in LLVM. What I am trying to do is create a variable argument function and then add the logic to manipulate the variable arguments. For example: /\*can do this\*/ int foo(int a, ...) { double var1; //can't figure out how to add any of this using llvm va_list ap; va_start(ap, a); va_arg(var1,double); va_end(ap); } Creating the function type is easy because I just set the vararg boolean to true. What do I do after that?
I always use clang to check what it needs to convert for c/c++ lang. Use llvm instruction va_arg and intinsics llvm.va_start, llvm.va_end, llvm.va_copy to use llvm variable argument support. you also need target-specific value type “va_list” for functions that operates on arguments that use this. ; This struct is different for every platform. For most platforms, ; it is merely an i8*. %struct.va_list = type { i8* } ; For Unix x86_64 platforms, va_list is the following struct: ; %struct.va_list = type { i32, i32, i8*, i8* } ref http://llvm.org/docs/LangRef.html#variable-argument-handling-intrinsics for your listed code, ; ModuleID = 'test.c' target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" target triple = "x86_64-pc-linux-gnu" %struct.__va_list_tag = type { i32, i32, i8*, i8* } ; Function Attrs: nounwind uwtable define i32 #foo(i32 %a, ...) #0 { %1 = alloca i32, align 4 %2 = alloca i32, align 4 %var1 = alloca double, align 8 %ap = alloca [1 x %struct.__va_list_tag], align 16 store i32 %a, i32* %2, align 4 %3 = getelementptr inbounds [1 x %struct.__va_list_tag]* %ap, i32 0, i32 0 %4 = bitcast %struct.__va_list_tag* %3 to i8* call void #llvm.va_start(i8* %4) %5 = getelementptr inbounds [1 x %struct.__va_list_tag]* %ap, i32 0, i32 0 %6 = getelementptr inbounds %struct.__va_list_tag* %5, i32 0, i32 1 %7 = load i32* %6 %8 = icmp ule i32 %7, 160 br i1 %8, label %9, label %15 ; <label>:9 ; preds = %0 %10 = getelementptr inbounds %struct.__va_list_tag* %5, i32 0, i32 3 %11 = load i8** %10 %12 = getelementptr i8* %11, i32 %7 %13 = bitcast i8* %12 to double* %14 = add i32 %7, 16 store i32 %14, i32* %6 br label %20 ; <label>:15 ; preds = %0 %16 = getelementptr inbounds %struct.__va_list_tag* %5, i32 0, i32 2 %17 = load i8** %16 %18 = bitcast i8* %17 to double* %19 = getelementptr i8* %17, i32 8 store i8* %19, i8** %16 br label %20 ; <label>:20 ; preds = %15, %9 %21 = phi double* [ %13, %9 ], [ %18, %15 ] %22 = load double* %21 %23 = getelementptr inbounds [1 x %struct.__va_list_tag]* %ap, i32 0, i32 0 %24 = bitcast %struct.__va_list_tag* %23 to i8* call void #llvm.va_end(i8* %24) %25 = load i32* %1 ret i32 %25 } ; Function Attrs: nounwind declare void #llvm.va_start(i8*) #1 ; Function Attrs: nounwind declare void #llvm.va_end(i8*) #1 ; Function Attrs: nounwind uwtable define i32 #main() #0 { ret i32 0 }