[reactos] 01/01: [CRT] Fix link issues with __ftol2 when compiling for NT6

[Timo Kreuzer]

https://git.reactos.org/?p=reactos.git;a=commitdiff;h=f80d978fc039ceb1bc070…

commit f80d978fc039ceb1bc070d6e8a5b6eca5abe2f13
Author:     Timo Kreuzer <timo.kreuzer(a)reactos.org>
AuthorDate: Thu Aug 29 20:57:30 2024 +0300
Commit:     Timo Kreuzer <timo.kreuzer(a)reactos.org>
CommitDate: Fri Aug 30 06:29:13 2024 +0300

    [CRT] Fix link issues with __ftol2 when compiling for NT6
    
    __ftol2 is exported from msvcrt on NT6+, not from ntdll for some reason. So native
apps still need to statically link _ftol2 and _ftoul2_legacy, but apps linking to msvcrt
only need to statically link _ftoul2_legacy (via msvcrtex), when on NT6+.
---
 sdk/lib/crt/CMakeLists.txt                         |  1 +
 sdk/lib/crt/math/i386/ftol2_asm.s                  | 66 ++--------------------
 .../math/i386/{ftol2_asm.s => ftoul2_legacy_asm.s} | 15 +----
 sdk/lib/crt/math/math.cmake                        |  1 +
 sdk/lib/crt/msvcrtex.cmake                         |  3 +-
 5 files changed, 12 insertions(+), 74 deletions(-)

diff --git a/sdk/lib/crt/CMakeLists.txt b/sdk/lib/crt/CMakeLists.txt
index 6c38c518e56..740b9aec154 100644
--- a/sdk/lib/crt/CMakeLists.txt
+++ b/sdk/lib/crt/CMakeLists.txt
@@ -49,6 +49,7 @@ target_compile_definitions(user32_wsprintf PRIVATE _USER32_WSPRINTF)
 if(MSVC AND ARCH STREQUAL "i386")
     add_asm_files(ftol2_asm
         math/i386/ftol2_asm.s
+        math/i386/ftoul2_legacy_asm.s
     )
     add_library(ftol2 ${ftol2_asm})
     set_target_properties(ftol2 PROPERTIES LINKER_LANGUAGE "C")
diff --git a/sdk/lib/crt/math/i386/ftol2_asm.s b/sdk/lib/crt/math/i386/ftol2_asm.s
index a15a7031abc..974d6f5a468 100644
--- a/sdk/lib/crt/math/i386/ftol2_asm.s
+++ b/sdk/lib/crt/math/i386/ftol2_asm.s
@@ -1,8 +1,10 @@
 /*
- * PROJECT:     ReactOS CRT
- * LICENSE:     MIT (https://spdx.org/licenses/MIT)
- * PURPOSE:     Floating point conversion routines
- * COPYRIGHT:   Copyright 2024 Timo Kreuzer <timo.kreuzer(a)reactos.org>
+ * COPYRIGHT:         See COPYING in the top level directory
+ * PROJECT:           ReactOS kernel
+ * PURPOSE:           Run-Time Library
+ * FILE:              lib/sdk/crt/math/i386/ftol2_asm.s
+ * PROGRAMER:
+ *
  */
 
 #include <asm.inc>
@@ -10,7 +12,6 @@
 EXTERN __ftol:PROC
 PUBLIC __ftol2
 PUBLIC __ftol2_sse
-PUBLIC __ftoul2_legacy
 
 /* FUNCTIONS ***************************************************************/
 .code
@@ -24,59 +25,4 @@ __ftol2:
 __ftol2_sse:
     jmp __ftol
 
-__real@43e0000000000000:
-    .quad HEX(43e0000000000000)
-
-__ftoul2_legacy:
-
-    /* Compare the fp number, passed in st(0), against (LLONG_MAX + 1)
-       aka 9223372036854775808.0 (which is 0x43e0000000000000 in double format).
-       If it is smaller, it fits into an __int64, so we can pass it to _ftol2.
-       After this the original fp value has moved to st(1) */
-    fld qword ptr [__real@43e0000000000000]
-    fcom
-
-    /* Put the comparison result bits into ax */
-    fnstsw ax
-
-    /* Here we test the bits for c0 (0x01) and c3 (0x40).
-       We check the parity bit after the test. If it is set,
-       an even number of bits were set.
-       If both are 0, st(1) < st(0), i.e. our value is ok.
-       If both are 1, the value is NaN/Inf and we let _ftol2 handle it. */
-    test ah, HEX(41)
-    jnp __ftoul2_legacy2
-
-    /* Clean up the fp stack and forward to _ftol2 */
-    fstp st(0)
-    jmp __ftol2
-
-__ftoul2_legacy2:
-
-    /* Subtract (LLONG_MAX + 1) from the given fp value and put the result in st(1).
-       st(0) = 9223372036854775808.0
-       st(1) = original fp value - 9223372036854775808.0 */
-    fsub st(1), st(0)
-
-    /* Compare the result to (LLONG_MAX + 1) again and pop the fp stack.
-       Here we check, whether c0 and c3 are both 0, indicating that st(0) > st(1),
-       i.e. fp - (LLONG_MAX + 1) < (LLONG_MAX + 1) */
-    fcomp
-    fnstsw ax
-    test ah, HEX(41)
-    jnz __ftoul2_legacy3
-
-    /* We have established that fp - (LLONG_MAX + 1) fits into an __int64,
-       so pass that to _ftol2 and manually add the difference to the result */
-    call __ftol2
-    add edx, HEX(80000000)
-    ret
-
-__ftoul2_legacy3:
-
-    /* The value is too large, just return the error value */
-    xor eax, eax
-    mov edx, HEX(80000000)
-    ret
-
 END
diff --git a/sdk/lib/crt/math/i386/ftol2_asm.s
b/sdk/lib/crt/math/i386/ftoul2_legacy_asm.s
similarity index 87%
copy from sdk/lib/crt/math/i386/ftol2_asm.s
copy to sdk/lib/crt/math/i386/ftoul2_legacy_asm.s
index a15a7031abc..432d95435f1 100644
--- a/sdk/lib/crt/math/i386/ftol2_asm.s
+++ b/sdk/lib/crt/math/i386/ftoul2_legacy_asm.s
@@ -7,26 +7,15 @@
 
 #include <asm.inc>
 
-EXTERN __ftol:PROC
-PUBLIC __ftol2
-PUBLIC __ftol2_sse
-PUBLIC __ftoul2_legacy
+EXTERN __ftol2:PROC
 
 /* FUNCTIONS ***************************************************************/
 .code
 
-/*
- * This routine is called by MSVC-generated code to convert from floating point
- * to integer representation. The floating point number to be converted is
- * on the top of the floating point stack.
- */
-__ftol2:
-__ftol2_sse:
-    jmp __ftol
-
 __real@43e0000000000000:
     .quad HEX(43e0000000000000)
 
+PUBLIC __ftoul2_legacy
 __ftoul2_legacy:
 
     /* Compare the fp number, passed in st(0), against (LLONG_MAX + 1)
diff --git a/sdk/lib/crt/math/math.cmake b/sdk/lib/crt/math/math.cmake
index 5821259646a..3a6c69995b5 100644
--- a/sdk/lib/crt/math/math.cmake
+++ b/sdk/lib/crt/math/math.cmake
@@ -40,6 +40,7 @@ if(ARCH STREQUAL "i386")
         math/i386/floor_asm.s
         math/i386/ftol_asm.s
         math/i386/ftol2_asm.s
+        math/i386/ftoul2_legacy_asm.s
         math/i386/log_asm.s
         math/i386/log10_asm.s
         math/i386/pow_asm.s
diff --git a/sdk/lib/crt/msvcrtex.cmake b/sdk/lib/crt/msvcrtex.cmake
index 6377cfa688b..232f7bda6bd 100644
--- a/sdk/lib/crt/msvcrtex.cmake
+++ b/sdk/lib/crt/msvcrtex.cmake
@@ -47,7 +47,8 @@ if(ARCH STREQUAL "i386")
     endif()
     if(MSVC AND DLL_EXPORT_VERSION LESS 0x600)
         list(APPEND MSVCRTEX_ASM_SOURCE
-            except/i386/__CxxFrameHandler3.s)
+            except/i386/__CxxFrameHandler3.s
+            math/i386/ftoul2_legacy_asm.s)
         list(APPEND MSVCRTEX_SOURCE
             except/i386/CxxHandleV8Frame.c)
     endif()