dump.c

#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>

//void _dump_debug_trace() {}
//void _dump_string(void *pointerToString) {}

// This will work for GCC and clang for x64
// #define GET_STACK_POINTER(NAME)   uintptr_t NAME; asm("mov %%rsp, %0": "=r" ( NAME )); 

#define FRAME_SIZE 4096

#define dump_frame                                                             \
  dump("Current Stack Frame:", __builtin_frame_address(0), FRAME_SIZE);        \
  dump("Current Stack Frame:", __builtin_frame_address(1), FRAME_SIZE);


void dump(char *desc, void *pointerToValue, int len) {
  int i;
  unsigned char buff[17];
  unsigned char *pc = (unsigned char *)pointerToValue;

  // Output description if given.
  if (desc != NULL)
    printf("%s:\n", desc);

  // Process every byte in the data.
  for (i = 0; i < len; i++) {
    // Multiple of 16 means new line (with line offset).

    if ((i % 16) == 0) {
      // Just don't print ASCII for the zeroth line.
      if (i != 0)
        printf("  %s\n", buff);

      // Output the offset.
      printf("  %04x ", i);
    }

    // Now the hex code for the specific character.
    printf(" %02x", pc[i]);

    // And store a printable ASCII character for later.
    if ((pc[i] < 0x20) || (pc[i] > 0x7e)) {
      buff[i % 16] = '.';
    } else {
      buff[i % 16] = pc[i];
    }

    buff[(i % 16) + 1] = '\0';
  }

  // Pad out last line if not exactly 16 characters.
  while ((i % 16) != 0) {
    printf("   ");
    i++;
  }

  // And print the final ASCII bit.
  printf("  %s\n", buff);
}

stackptr-test.c

#include <stdio.h>
#include "dump.c"

void
random_stack_increase(int depth)
{
  if(depth < 3) { 
    random_stack_increase(depth++);
  } else { 
    dump_frame; // dump.c
    return;
  }
}

void
main(void)
{
  int *a = malloc(100);
  int *b = malloc(200);

  int z = a < b;

  printf("%i", z);

  char f[3] = "abc";
  dump("abc", &f, 5);

  char *g = malloc(1024);

  #if  __GNUC__
  printf("Hello world!\n");
  #else
  printf("You suck\n");
  #endif
}

stackptr-test.ll

; ModuleID = 'test.c'
source_filename = "test.c"
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-pc-linux-gnu"

@.str = private unnamed_addr constant [5 x i8] c"%s:\0A\00", align 1
@.str.1 = private unnamed_addr constant [6 x i8] c"  %s\0A\00", align 1
@.str.2 = private unnamed_addr constant [8 x i8] c"  %04x \00", align 1
@.str.3 = private unnamed_addr constant [6 x i8] c" %02x\00", align 1
@.str.4 = private unnamed_addr constant [4 x i8] c"   \00", align 1
@.str.5 = private unnamed_addr constant [21 x i8] c"Current Stack Frame:\00", align 1
@.str.6 = private unnamed_addr constant [3 x i8] c"%i\00", align 1
@__const.main.f = private unnamed_addr constant [3 x i8] c"abc", align 1
@.str.7 = private unnamed_addr constant [4 x i8] c"abc\00", align 1
@.str.8 = private unnamed_addr constant [14 x i8] c"Hello world!\0A\00", align 1

; Function Attrs: noinline nounwind optnone uwtable
define dso_local void @dump(i8* %0, i8* %1, i32 %2) #0 {
  %4 = alloca i8*, align 8
  %5 = alloca i8*, align 8
  %6 = alloca i32, align 4
  %7 = alloca i32, align 4
  %8 = alloca [17 x i8], align 16
  %9 = alloca i8*, align 8
  store i8* %0, i8** %4, align 8
  store i8* %1, i8** %5, align 8
  store i32 %2, i32* %6, align 4
  %10 = load i8*, i8** %5, align 8
  store i8* %10, i8** %9, align 8
  %11 = load i8*, i8** %4, align 8
  %12 = icmp ne i8* %11, null
  br i1 %12, label %13, label %16

13:                                               ; preds = %3
  %14 = load i8*, i8** %4, align 8
  %15 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str, i64 0, i64 0), i8* %14)
  br label %16

16:                                               ; preds = %13, %3
  store i32 0, i32* %7, align 4
  br label %17

17:                                               ; preds = %78, %16
  %18 = load i32, i32* %7, align 4
  %19 = load i32, i32* %6, align 4
  %20 = icmp slt i32 %18, %19
  br i1 %20, label %21, label %81

21:                                               ; preds = %17
  %22 = load i32, i32* %7, align 4
  %23 = srem i32 %22, 16
  %24 = icmp eq i32 %23, 0
  br i1 %24, label %25, label %34

25:                                               ; preds = %21
  %26 = load i32, i32* %7, align 4
  %27 = icmp ne i32 %26, 0
  br i1 %27, label %28, label %31

28:                                               ; preds = %25
  %29 = getelementptr inbounds [17 x i8], [17 x i8]* %8, i64 0, i64 0
  %30 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.1, i64 0, i64 0), i8* %29)
  br label %31

31:                                               ; preds = %28, %25
  %32 = load i32, i32* %7, align 4
  %33 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([8 x i8], [8 x i8]* @.str.2, i64 0, i64 0), i32 %32)
  br label %34

34:                                               ; preds = %31, %21
  %35 = load i8*, i8** %9, align 8
  %36 = load i32, i32* %7, align 4
  %37 = sext i32 %36 to i64
  %38 = getelementptr inbounds i8, i8* %35, i64 %37
  %39 = load i8, i8* %38, align 1
  %40 = zext i8 %39 to i32
  %41 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.3, i64 0, i64 0), i32 %40)
  %42 = load i8*, i8** %9, align 8
  %43 = load i32, i32* %7, align 4
  %44 = sext i32 %43 to i64
  %45 = getelementptr inbounds i8, i8* %42, i64 %44
  %46 = load i8, i8* %45, align 1
  %47 = zext i8 %46 to i32
  %48 = icmp slt i32 %47, 32
  br i1 %48, label %57, label %49

49:                                               ; preds = %34
  %50 = load i8*, i8** %9, align 8
  %51 = load i32, i32* %7, align 4
  %52 = sext i32 %51 to i64
  %53 = getelementptr inbounds i8, i8* %50, i64 %52
  %54 = load i8, i8* %53, align 1
  %55 = zext i8 %54 to i32
  %56 = icmp sgt i32 %55, 126
  br i1 %56, label %57, label %62

57:                                               ; preds = %49, %34
  %58 = load i32, i32* %7, align 4
  %59 = srem i32 %58, 16
  %60 = sext i32 %59 to i64
  %61 = getelementptr inbounds [17 x i8], [17 x i8]* %8, i64 0, i64 %60
  store i8 46, i8* %61, align 1
  br label %72

62:                                               ; preds = %49
  %63 = load i8*, i8** %9, align 8
  %64 = load i32, i32* %7, align 4
  %65 = sext i32 %64 to i64
  %66 = getelementptr inbounds i8, i8* %63, i64 %65
  %67 = load i8, i8* %66, align 1
  %68 = load i32, i32* %7, align 4
  %69 = srem i32 %68, 16
  %70 = sext i32 %69 to i64
  %71 = getelementptr inbounds [17 x i8], [17 x i8]* %8, i64 0, i64 %70
  store i8 %67, i8* %71, align 1
  br label %72

72:                                               ; preds = %62, %57
  %73 = load i32, i32* %7, align 4
  %74 = srem i32 %73, 16
  %75 = add nsw i32 %74, 1
  %76 = sext i32 %75 to i64
  %77 = getelementptr inbounds [17 x i8], [17 x i8]* %8, i64 0, i64 %76
  store i8 0, i8* %77, align 1
  br label %78

78:                                               ; preds = %72
  %79 = load i32, i32* %7, align 4
  %80 = add nsw i32 %79, 1
  store i32 %80, i32* %7, align 4
  br label %17

81:                                               ; preds = %17
  br label %82

82:                                               ; preds = %86, %81
  %83 = load i32, i32* %7, align 4
  %84 = srem i32 %83, 16
  %85 = icmp ne i32 %84, 0
  br i1 %85, label %86, label %90

86:                                               ; preds = %82
  %87 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.4, i64 0, i64 0))
  %88 = load i32, i32* %7, align 4
  %89 = add nsw i32 %88, 1
  store i32 %89, i32* %7, align 4
  br label %82

90:                                               ; preds = %82
  %91 = getelementptr inbounds [17 x i8], [17 x i8]* %8, i64 0, i64 0
  %92 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([6 x i8], [6 x i8]* @.str.1, i64 0, i64 0), i8* %91)
  ret void
}

declare dso_local i32 @printf(i8*, ...) #1

; Function Attrs: noinline nounwind optnone uwtable
define dso_local void @random_stack_increase(i32 %0) #0 {
  %2 = alloca i32, align 4
  store i32 %0, i32* %2, align 4
  %3 = load i32, i32* %2, align 4
  %4 = icmp slt i32 %3, 3
  br i1 %4, label %5, label %8

5:                                                ; preds = %1
  %6 = load i32, i32* %2, align 4
  %7 = add nsw i32 %6, 1
  store i32 %7, i32* %2, align 4
  call void @random_stack_increase(i32 %6)
  br label %11

8:                                                ; preds = %1
  %9 = call i8* @llvm.frameaddress.p0i8(i32 0)
  call void @dump(i8* getelementptr inbounds ([21 x i8], [21 x i8]* @.str.5, i64 0, i64 0), i8* %9, i32 4096)
  %10 = call i8* @llvm.frameaddress.p0i8(i32 1)
  call void @dump(i8* getelementptr inbounds ([21 x i8], [21 x i8]* @.str.5, i64 0, i64 0), i8* %10, i32 4096)
  br label %11

11:                                               ; preds = %8, %5
  ret void
}

; Function Attrs: nounwind readnone
declare i8* @llvm.frameaddress.p0i8(i32 immarg) #2

; Function Attrs: noinline nounwind optnone uwtable
define dso_local void @main() #0 {
  %1 = alloca i32*, align 8
  %2 = alloca i32*, align 8
  %3 = alloca i32, align 4
  %4 = alloca [3 x i8], align 1
  %5 = alloca i8*, align 8
  %6 = call noalias i8* @malloc(i64 100) #5
  %7 = bitcast i8* %6 to i32*
  store i32* %7, i32** %1, align 8
  %8 = call noalias i8* @malloc(i64 200) #5
  %9 = bitcast i8* %8 to i32*
  store i32* %9, i32** %2, align 8
  %10 = load i32*, i32** %1, align 8
  %11 = load i32*, i32** %2, align 8
  %12 = icmp ult i32* %10, %11
  %13 = zext i1 %12 to i32
  store i32 %13, i32* %3, align 4
  %14 = load i32, i32* %3, align 4
  %15 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.6, i64 0, i64 0), i32 %14)
  %16 = bitcast [3 x i8]* %4 to i8*
  call void @llvm.memcpy.p0i8.p0i8.i64(i8* align 1 %16, i8* align 1 getelementptr inbounds ([3 x i8], [3 x i8]* @__const.main.f, i32 0, i32 0), i64 3, i1 false)
  %17 = bitcast [3 x i8]* %4 to i8*
  call void @dump(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.7, i64 0, i64 0), i8* %17, i32 5)
  %18 = call noalias i8* @malloc(i64 1024) #5
  store i8* %18, i8** %5, align 8
  %19 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([14 x i8], [14 x i8]* @.str.8, i64 0, i64 0))
  ret void
}

; Function Attrs: nounwind
declare dso_local noalias i8* @malloc(i64) #3

; Function Attrs: argmemonly nounwind willreturn
declare void @llvm.memcpy.p0i8.p0i8.i64(i8* noalias nocapture writeonly, i8* noalias nocapture readonly, i64, i1 immarg) #4

attributes #0 = { noinline nounwind optnone uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "frame-pointer"="all" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #1 = { "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "frame-pointer"="all" "less-precise-fpmad"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #2 = { nounwind readnone }
attributes #3 = { nounwind "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "frame-pointer"="all" "less-precise-fpmad"="false" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="true" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "tune-cpu"="generic" "unsafe-fp-math"="false" "use-soft-float"="false" }
attributes #4 = { argmemonly nounwind willreturn }
attributes #5 = { nounwind }

!llvm.module.flags = !{!0}
!llvm.ident = !{!1}

!0 = !{i32 1, !"wchar_size", i32 4}
!1 = !{!"Debian clang version 12.0.0-++20200909020009+d4b88ac1658-1~exp1~20200909120636.3474"}