Make fixupobj work on Windows

This fixes a regression with recent cosmocc toolchain releases that
causes fixupobj to fail with "ifunc ftruncate #1 failed" on Windows

Author: jart

build/bootstrap/fixupobj

@@ -61,6 +61,12 @@
 #define _X86_CC_AVX512BF16 0
 #endif
 
+#ifdef __AVX512FP16__
+#define _X86_CC_AVX512FP16 1
+#else
+#define _X86_CC_AVX512FP16 0
+#endif
+
 #ifdef __AVX512VBMI__
 #define _X86_CC_AVX512VBMI 1
 #else

libc/nexgen32e/x86compiler.h

@@ -42,6 +42,7 @@
 #define X86_AVX512VL             7H,        EBX, 31, 0
 #define X86_AVX512_4FMAPS        7H,        EDX,  3, 0
 #define X86_AVX512_4VNNIW        7H,        EDX,  2, _X86_CC_AVX5124VNNIW
+#define X86_AVX512_FP16          7H,        EDX, 23, _X86_CC_AVX512FP16
 #define X86_AVX512_BF16          7H,        EAX,  5, _X86_CC_AVX512BF16
 #define X86_AVX512_BITALG        7H,        ECX, 12, 0
 #define X86_AVX512_VBMI2         7H,        ECX,  6, 0

libc/nexgen32e/x86feature.h

@@ -33,6 +33,7 @@
 #include "libc/log/log.h"
 #include "libc/macros.internal.h"
 #include "libc/mem/gc.h"
+#include "libc/mem/mem.h"
 #include "libc/runtime/runtime.h"
 #include "libc/serialize.h"
 #include "libc/stdalign.internal.h"
@@ -71,6 +72,21 @@ static wontreturn void Die(const char *reason) {
   exit(1);
 }
 
+static wontreturn void DieOom(void) {
+  Die("out of memory");
+}
+
+static void *Malloc(size_t n) {
+  void *p;
+  if (!(p = malloc(n))) DieOom();
+  return p;
+}
+
+static void *Realloc(void *p, size_t n) {
+  if (!(p = realloc(p, n))) DieOom();
+  return p;
+}
+
 static wontreturn void SysExit(const char *func) {
   const char *errstr;
   if (!(errstr = _strerdoc(errno))) errstr = "EUNKNOWN";
@@ -515,10 +531,7 @@ static void GenerateIfuncInit(void) {
   // remap file so it has more space
   if (elf->e_shnum + 2 > 65535) Die("too many sections");
   size_t reserve_size = esize + 32 * 1024 * 1024;
-  if (ftruncate(fildes, reserve_size)) SysExit("ifunc ftruncate #1");
-  elf = mmap((char *)elf, reserve_size, PROT_READ | PROT_WRITE,
-             MAP_FIXED | MAP_SHARED, fildes, 0);
-  if (elf == MAP_FAILED) SysExit("ifunc mmap");
+  elf = Realloc(elf, reserve_size);
 
   // duplicate section name strings table to end of file
   Elf64_Shdr *shdrstr_shdr = (Elf64_Shdr *)((char *)elf + elf->e_shoff +
@@ -591,8 +604,6 @@ static void GenerateIfuncInit(void) {
   memcpy((char *)elf + esize, code, code_i);
   esize += code_i;
   unassert(esize == code_shdr->sh_offset + code_shdr->sh_size);
-
-  if (ftruncate(fildes, esize)) SysExit("ifunc ftruncate #1");
 }
 
 // when __attribute__((__target_clones__(...))) is used, static binaries
@@ -622,9 +633,9 @@ static void FixupObject(void) {
     SysExit("lseek");
   }
   if (esize) {
-    if ((elf = mmap((void *)0x032100000000, esize, PROT_READ | PROT_WRITE,
-                    MAP_FIXED | MAP_SHARED, fildes, 0)) == MAP_FAILED) {
-      SysExit("mmap");
+    elf = Malloc(esize);
+    if (pread(fildes, elf, esize, 0) != esize) {
+      SysExit("pread");
     }
     if (!IsElf64Binary(elf, esize)) {
       Die("not an elf64 binary");
@@ -654,13 +665,10 @@ static void FixupObject(void) {
         PurgeIfuncSections();
         RelinkZipFiles();
       }
-      if (msync(elf, esize, MS_ASYNC | MS_INVALIDATE)) {
-        SysExit("msync");
+      if (pwrite(fildes, elf, esize, 0) != esize) {
+        SysExit("pwrite");
       }
     }
-    if (munmap(elf, esize)) {
-      SysExit("munmap");
-    }
   }
   if (close(fildes)) {
     SysExit("close");

tool/build/fixupobj.c

@@ -220,7 +220,13 @@
            "__m256i"
            "__m256_u"
            "__m256d_u"
-           "__m256i_u"))
+           "__m256i_u"
+           "__m512"
+           "__m512d"
+           "__m512i"
+           "__m512_u"
+           "__m512d_u"
+           "__m512i_u"))
 
 )
     (concat "\\_<"

tool/emacs/cosmo-c-types.el

@@ -55,6 +55,7 @@
     "__AVX512CD__"
     "__AVX512DQ__"
     "__AVX512BF16__"
+    "__AVX512FP16__"
     "__AVX512IFMA__"
     "__AVX5124VNNIW__"
     "__AVX512VBMI__"

tool/emacs/cosmo-cpp-constants.el

@@ -188,6 +188,7 @@ int main(int argc, char *argv[]) {
   CANIUSE(AVX512VL);
   CANIUSE(AVX512_4FMAPS);
   CANIUSE(AVX512_4VNNIW);
+  CANIUSE(AVX512_FP16);
   CANIUSE(AVX512_BF16);
   CANIUSE(AVX512_BITALG);
   CANIUSE(AVX512_VBMI2);