_Iflot(fptr, length) float *fptr;
int length;
{
  char temp[75];
  int _Inodg();
  float x;
  double atof();
  if (_Isstr(temp, length, _Inodg) < 0)
    return (-1);
  x = atof(temp);
  if (fptr == 0)
    return (0);
  *fptr = x;
  return (1);
}


x86 assembly (clang, -O0):
<_Iflot>:
push   %rbp
mov    %rsp,%rbp
sub    $0x70,%rsp
mov    %rdi,-0x10(%rbp)
mov    %esi,-0x14(%rbp)
lea    -0x60(%rbp),%rdi
mov    -0x14(%rbp),%esi
mov    0x2ea3(%rip),%rdx
mov    $0x0,%al
call   1040 <_Isstr@plt>
cmp    $0x0,%eax
jge    1159 <_Iflot+0x39>
movl   $0xffffffff,-0x4(%rbp)
jmp    1198 <_Iflot+0x78>
lea    -0x60(%rbp),%rdi
mov    $0x0,%al
call   1030 <atof@plt>
cvtsd2ss %xmm0,%xmm0
movss  %xmm0,-0x64(%rbp)
cmpq   $0x0,-0x10(%rbp)
jne    1184 <_Iflot+0x64>
movl   $0x0,-0x4(%rbp)
jmp    1198 <_Iflot+0x78>
movss  -0x64(%rbp),%xmm0
mov    -0x10(%rbp),%rax
movss  %xmm0,(%rax)
movl   $0x1,-0x4(%rbp)
mov    -0x4(%rbp),%eax
add    $0x70,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<_Iflot>:
push   %r14
push   %rbx
sub    $0x58,%rsp
mov    %rdi,%r14
mov    0x2eaf(%rip),%rdx
xor    %ebx,%ebx
mov    %rsp,%rdi
xor    %eax,%eax
call   1040 <_Isstr@plt>
test   %eax,%eax
js     1160 <_Iflot+0x40>
mov    %rsp,%rdi
xor    %eax,%eax
call   1030 <atof@plt>
test   %r14,%r14
je     1165 <_Iflot+0x45>
cvtsd2ss %xmm0,%xmm0
movss  %xmm0,(%r14)
mov    $0x1,%ebx
jmp    1165 <_Iflot+0x45>
mov    $0xffffffff,%ebx
mov    %ebx,%eax
add    $0x58,%rsp
pop    %rbx
pop    %r14
ret

LLVM IR (-O0):
define i32 @_Iflot(float* %0, i32 %1) {
%3 = alloca i32
%4 = alloca float*
%5 = alloca i32
%6 = alloca [75 x i8]
%7 = alloca float
store float* %0, float** %4
store i32 %1, i32* %5
%8 = getelementptr inbounds [75 x i8], [75 x i8]* %6, i64 0, i64 0
%9 = load i32, i32* %5
%10 = call i32 (i8*, i32, i32 (...)*, ...) bitcast (i32 (...)* @_Isstr to i32 (i8*, i32, i32 (...)*, ...)*)(i8* %8, i32 %9, i32 (...)* @_Inodg)
%11 = icmp slt i32 %10, 0
br i1 %11, label %12, label %13
12: ; preds = %2
store i32 -1, i32* %3
br label %23
13: ; preds = %2
%14 = getelementptr inbounds [75 x i8], [75 x i8]* %6, i64 0, i64 0
%15 = call double (i8*, ...) bitcast (double (...)* @atof to double (i8*, ...)*)(i8* %14)
%16 = fptrunc double %15 to float
store float %16, float* %7
%17 = load float*, float** %4
%18 = icmp eq float* %17, null
br i1 %18, label %19, label %20
19: ; preds = %13
store i32 0, i32* %3
br label %23
20: ; preds = %13
%21 = load float, float* %7
%22 = load float*, float** %4
store float %21, float* %22
store i32 1, i32* %3
br label %23
23: ; preds = %20, %19, %12
%24 = load i32, i32* %3
ret i32 %24
}

LLVM IR (-O2):
define i32 @_Iflot(float* writeonly %0, i32 %1) {
%3 = alloca [75 x i8]
%4 = getelementptr inbounds [75 x i8], [75 x i8]* %3, i64 0, i64 0
%5 = call i32 (i8*, i32, i32 (...)*, ...) bitcast (i32 (...)* @_Isstr to i32 (i8*, i32, i32 (...)*, ...)*)(i8* %4, i32 %1, i32 (...)* @_Inodg)
%6 = icmp slt i32 %5, 0
br i1 %6, label %12, label %7
7: ; preds = %2
%8 = call double (i8*, ...) bitcast (double (...)* @atof to double (i8*, ...)*)(i8* %4)
%9 = icmp eq float* %0, null
br i1 %9, label %12, label %10
10: ; preds = %7
%11 = fptrunc double %8 to float
store float %11, float* %0
br label %12
12: ; preds = %7, %2, %10
%13 = phi i32 [ 1, %10 ], [ -1, %2 ], [ 0, %7 ]
ret i32 %13
}