Show inlined standard functions as function call

[op2786]

Compilers sometimes makes standard functions (strlen, memcpy, strcat, memset, strcmp, memcmp etc) inline. I guess their code pattern can be recognized and replaced with pseudo call to function.

Example disassembly:

1800382a2  488dbda0120000     lea     rdi, [rbp+0x12a0 {Dst}]
1800382a9  33c0               xor     eax, eax  {0x0}
1800382ab  b90c010000         mov     ecx, 0x10c
1800382b0  f3aa               rep stosb byte [rdi]  {0x0}  {0x0}  {0x0}

Output in HLIL:

1800382a2          char (* rdi_1)[0x110] = &Dst
1800382b0          for (int64_t rcx_4 = 0x10c; rcx_4 != 0; rcx_4 = rcx_4 - 1) {
1800382b0              *rdi_1 = 0
1800382b0              rdi_1 = &(*rdi_1)[1]
1800382b0          }

Which can be replaced memset(Dst, 0, 0x10c). It may be related to #2185.

[fuzyll]

This is a subset of the functionality that would be required for #2185, so we're leaving this issue to track automatically resolving standard library calls that get inlined. The other issue tracks being able to make any HLIL code into an inlined function.

[plafosse]

Currently we have partial support for this feature. It is currently limited to "Constant Data" i.e. When a string or data is "usually" written to sequential stack locations. We recover these and display them as one of:

• [x] __builtin_strcpy
• [x] __builtin_strncpy
• [x] __builtin_memcpy
• [x] __builtin_wcscpy
• [x] __builtin_memset

Still TODO: Comparison functions:

• [ ] memcmp
• [ ] strcmp

Recovery of non-"Constant Data" functions:

• [ ] strlen
• [ ] strcpy
• [ ] strncpy
• [ ] memcpy
• [ ] memcmp
• [ ] wcscpy
• [ ] strcmp