81 lines
2.7 KiB
Plaintext
81 lines
2.7 KiB
Plaintext
; ModuleID = 'factorial.c'
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; source_filename = "factorial.c"
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; target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
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; target triple = "x86_64-pc-windows-msvc19.21.27702"
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; This is not strictly LLVM, as it uses the C library function "printf".
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; LLVM does not provide a way to print values, so the alternative would be
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; to just load the string into memory, and that would be boring.
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; Additional comments have been inserted, as well as changes made from the output produced by clang such as putting more meaningful labels for the jumps
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$"\01??_C@_04PEDNGLFL@?$CFld?6?$AA@" = comdat any
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@"\01??_C@_04PEDNGLFL@?$CFld?6?$AA@" = linkonce_odr unnamed_addr constant [5 x i8] c"%ld\0A\00", comdat, align 1
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;--- The declaration for the external C printf function.
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declare i32 @printf(i8*, ...)
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; Function Attrs: noinline nounwind optnone uwtable
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define i32 @factorial(i32) #0 {
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;-- local copy of n
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%2 = alloca i32, align 4
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;-- long result
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%3 = alloca i32, align 4
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;-- int i
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%4 = alloca i32, align 4
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;-- local n = parameter n
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store i32 %0, i32* %2, align 4
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;-- result = 1
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store i32 1, i32* %3, align 4
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;-- i = 1
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store i32 1, i32* %4, align 4
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br label %loop
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loop:
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;-- i <= n
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%5 = load i32, i32* %4, align 4
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%6 = load i32, i32* %2, align 4
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%7 = icmp sle i32 %5, %6
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br i1 %7, label %loop_body, label %exit
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loop_body:
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;-- result *= i
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%8 = load i32, i32* %4, align 4
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%9 = load i32, i32* %3, align 4
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%10 = mul nsw i32 %9, %8
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store i32 %10, i32* %3, align 4
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br label %loop_increment
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loop_increment:
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;-- ++i
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%11 = load i32, i32* %4, align 4
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%12 = add nsw i32 %11, 1
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store i32 %12, i32* %4, align 4
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br label %loop
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exit:
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;-- return result
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%13 = load i32, i32* %3, align 4
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ret i32 %13
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}
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; Function Attrs: noinline nounwind optnone uwtable
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define i32 @main() #0 {
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;-- factorial(5)
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%1 = call i32 @factorial(i32 5)
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;-- printf("%ld\n", factorial(5))
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%2 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([5 x i8], [5 x i8]* @"\01??_C@_04PEDNGLFL@?$CFld?6?$AA@", i32 0, i32 0), i32 %1)
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;-- return 0
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ret i32 0
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}
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attributes #0 = { noinline nounwind optnone uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="false" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
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!llvm.module.flags = !{!0, !1}
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!llvm.ident = !{!2}
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!0 = !{i32 1, !"wchar_size", i32 2}
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!1 = !{i32 7, !"PIC Level", i32 2}
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!2 = !{!"clang version 6.0.1 (tags/RELEASE_601/final)"}
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