void deallocate3D(double ***arr, int n1, int n2) {
  for (int i = 0; i < n1; ++i) {
    for (int j = 0; j < n2; ++j) {
      free(arr[i][j]);
    }
    free(arr[i]);
  }
  free(arr);
}


x86 assembly (clang, -O0):
<deallocate3D>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
mov    %rdi,-0x8(%rbp)
mov    %esi,-0xc(%rbp)
mov    %edx,-0x10(%rbp)
movl   $0x0,-0x14(%rbp)
mov    -0x14(%rbp),%eax
cmp    -0xc(%rbp),%eax
jge    118e <deallocate3D+0x7e>
movl   $0x0,-0x18(%rbp)
mov    -0x18(%rbp),%eax
cmp    -0x10(%rbp),%eax
jge    116f <deallocate3D+0x5f>
mov    -0x8(%rbp),%rax
movslq -0x14(%rbp),%rcx
mov    (%rax,%rcx,8),%rax
movslq -0x18(%rbp),%rcx
mov    (%rax,%rcx,8),%rdi
call   1030 <free@plt>
mov    -0x18(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x18(%rbp)
jmp    113c <deallocate3D+0x2c>
mov    -0x8(%rbp),%rax
movslq -0x14(%rbp),%rcx
mov    (%rax,%rcx,8),%rdi
call   1030 <free@plt>
mov    -0x14(%rbp),%eax
add    $0x1,%eax
mov    %eax,-0x14(%rbp)
jmp    1129 <deallocate3D+0x19>
mov    -0x8(%rbp),%rdi
call   1030 <free@plt>
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<deallocate3D>:
push   %rbp
push   %r15
push   %r14
push   %r13
push   %r12
push   %rbx
push   %rax
mov    %rdi,%r12
test   %esi,%esi
jle    1168 <deallocate3D+0x58>
mov    %edx,%r14d
mov    %esi,%r15d
mov    %edx,%r13d
xor    %ebx,%ebx
jmp    1142 <deallocate3D+0x32>
nop
mov    (%r12,%rbx,8),%rdi
call   1030 <free@plt>
add    $0x1,%rbx
cmp    %r15,%rbx
je     1168 <deallocate3D+0x58>
test   %r14d,%r14d
jle    1130 <deallocate3D+0x20>
xor    %ebp,%ebp
nopl   0x0(%rax)
mov    (%r12,%rbx,8),%rax
mov    (%rax,%rbp,8),%rdi
call   1030 <free@plt>
add    $0x1,%rbp
cmp    %rbp,%r13
jne    1150 <deallocate3D+0x40>
jmp    1130 <deallocate3D+0x20>
mov    %r12,%rdi
add    $0x8,%rsp
pop    %rbx
pop    %r12
pop    %r13
pop    %r14
pop    %r15
pop    %rbp
jmp    1030 <free@plt>

LLVM IR (-O0):
define void @deallocate3D(double*** %0, i32 %1, i32 %2) {
%4 = alloca double***
%5 = alloca i32
%6 = alloca i32
%7 = alloca i32
%8 = alloca i32
store double*** %0, double**** %4
store i32 %1, i32* %5
store i32 %2, i32* %6
store i32 0, i32* %7
br label %9
9: ; preds = %39, %3
%10 = load i32, i32* %7
%11 = load i32, i32* %5
%12 = icmp slt i32 %10, %11
br i1 %12, label %13, label %42
13: ; preds = %9
store i32 0, i32* %8
br label %14
14: ; preds = %29, %13
%15 = load i32, i32* %8
%16 = load i32, i32* %6
%17 = icmp slt i32 %15, %16
br i1 %17, label %18, label %32
18: ; preds = %14
%19 = load double***, double**** %4
%20 = load i32, i32* %7
%21 = sext i32 %20 to i64
%22 = getelementptr inbounds double**, double*** %19, i64 %21
%23 = load double**, double*** %22
%24 = load i32, i32* %8
%25 = sext i32 %24 to i64
%26 = getelementptr inbounds double*, double** %23, i64 %25
%27 = load double*, double** %26
%28 = bitcast double* %27 to i8*
br label %29
29: ; preds = %18
%30 = load i32, i32* %8
%31 = add nsw i32 %30, 1
store i32 %31, i32* %8
br label %14
32: ; preds = %14
%33 = load double***, double**** %4
%34 = load i32, i32* %7
%35 = sext i32 %34 to i64
%36 = getelementptr inbounds double**, double*** %33, i64 %35
%37 = load double**, double*** %36
%38 = bitcast double** %37 to i8*
br label %39
39: ; preds = %32
%40 = load i32, i32* %7
%41 = add nsw i32 %40, 1
store i32 %41, i32* %7
br label %9
42: ; preds = %9
%43 = load double***, double**** %4
%44 = bitcast double*** %43 to i8*
ret void
}

LLVM IR (-O2):
define void @deallocate3D(double*** nocapture %0, i32 %1, i32 %2) {
%4 = icmp sgt i32 %1, 0
br i1 %4, label %5, label %13
5: ; preds = %3
%6 = icmp sgt i32 %2, 0
%7 = zext i32 %1 to i64
%8 = zext i32 %2 to i64
br label %9
9: ; preds = %5, %15
%10 = phi i64 [ 0, %5 ], [ %19, %15 ]
br i1 %6, label %11, label %15
11: ; preds = %9
%12 = getelementptr inbounds double**, double*** %0, i64 %10
br label %21
13: ; preds = %15, %3
%14 = bitcast double*** %0 to i8*
tail call void @free(i8* %14)
ret void
15: ; preds = %21, %9
%16 = getelementptr inbounds double**, double*** %0, i64 %10
%17 = bitcast double*** %16 to i8**
%18 = load i8*, i8** %17
tail call void @free(i8* %18)
%19 = add nuw nsw i64 %10, 1
%20 = icmp eq i64 %19, %7
br i1 %20, label %13, label %9
21: ; preds = %11, %21
%22 = phi i64 [ 0, %11 ], [ %27, %21 ]
%23 = load double**, double*** %12
%24 = getelementptr inbounds double*, double** %23, i64 %22
%25 = bitcast double** %24 to i8**
%26 = load i8*, i8** %25
tail call void @free(i8* %26)
%27 = add nuw nsw i64 %22, 1
%28 = icmp eq i64 %27, %8
br i1 %28, label %15, label %21
}