Changeset 83886 in vbox for trunk/src/VBox/Runtime/common/string/RTStrEnd.asm

Timestamp:

Apr 21, 2020 11:14:20 AM (5 years ago)

Author:

vboxsync

Message:

IPRT: Implement RTStrEnd in assembly & C++, drop the inlining. memchr from VC++ 14.1 cannot deal wtih RTSTR_MAX on unaligned string, it may step into an electric fence page after the end of the string. bugref:8489

File:

• trunk/src/VBox/Runtime/common/string/RTStrEnd.asm (copied) (copied from trunk/src/VBox/Runtime/common/string/memchr.asm ) (3 diffs)

trunk/src/VBox/Runtime/common/string/RTStrEnd.asm

@@ -1 +1 @@
 ; $Id$
 ;; @file
-; IPRT - No-CRT memchr - AMD64 & X86.
+; IPRT - RTStrEnd - AMD64 & X86.
 ;
 
@@ -30 +30 @@
 
 ;;
-; @param    pv      gcc: rdi  msc: ecx  x86:[esp+4]   wcall: eax
-; @param    ch      gcc: esi  msc: edx  x86:[esp+8]   wcall: edx
-; @param    cb      gcc: rdx  msc: r8   x86:[esp+0ch] wcall: ebx
-RT_NOCRT_BEGINPROC memchr
+; @param    pszString   gcc: rdi  msc: rcx  x86:[esp+4]   wcall: eax
+; @param    cchMax      gcc: rsi  msc: rdx  x86:[esp+8]   wcall: edx
+;
+BEGINPROC_EXPORTED RTStrEnd
         cld
 %ifdef RT_ARCH_AMD64
  %ifdef ASM_CALL64_MSC
-        or      r8, r8
+        or      rdx, rdx
         jz      .not_found_early
 
         mov     r9, rdi                 ; save rdi
-        mov     eax, edx
         mov     rdi, rcx
-        mov     rcx, r8
+        mov     rcx, rdx
  %else
-        mov     rcx, rdx
+        mov     rcx, rsi
         jrcxz   .not_found_early
-
-        mov     eax, esi
  %endif
 
 %else
  %ifdef ASM_CALL32_WATCOM
-        mov     ecx, ebx
+        mov     ecx, edx
         jecxz   .not_found_early
-        xchg    eax, edx
-        xchg    edi, edx                ; load and save edi.
+        mov     edx, edi                ; save rdi
+        mov     edi, eax
  %else
-        mov     ecx, [esp + 0ch]
+        mov     ecx, [esp + 8]
         jecxz   .not_found_early
         mov     edx, edi                ; save edi
-        mov     eax, [esp + 8]
         mov     edi, [esp + 4]
  %endif
 %endif
+        xor     eax, eax                ; we're searching for zero
 
         ; do the search
@@ -90 +87 @@
         xor     eax, eax
         ret
-ENDPROC RT_NOCRT(memchr)
+ENDPROC RTStrEnd