From 50b040ef83252730d75463bdeea589294e698532 Mon Sep 17 00:00:00 2001
From: grischka <grischka>
Date: Sat, 19 Dec 2009 22:40:28 +0100
Subject: [PATCH] win64: add tiny unwind data for setjmp/longjmp

This enables native unwind semantics with longjmp on
win64 by putting an entry into the .pdata section for
each compiled fuction.

Also, the function now use a fixed stack and store arguments
into X(%rsp) rather than using push.
---
 i386-asm.c             |   4 +
 tcc.h                  |   7 ++
 tccpe.c                |  62 ++++++++-
 tccrun.c               |   7 ++
 win32/include/_mingw.h |   2 +-
 win32/lib/chkstk.S     |  14 ++-
 x86_64-gen.c           | 336 ++++++++++++++++++++++++++++++++++---------------
 7 files changed, 322 insertions(+), 110 deletions(-)

diff --git a/i386-asm.c b/i386-asm.c
index a378191b..075d2eab 100644
--- a/i386-asm.c
+++ b/i386-asm.c
@@ -426,6 +426,10 @@ static void gen_disp32(ExprValue *pe)
            elimination in the linker */
         gen_le32(pe->v + sym->jnext - ind - 4);
     } else {
+        if (sym && sym->type.t == VT_VOID) {
+            sym->type.t = VT_FUNC;
+            sym->type.ref = NULL;
+        }
         gen_addrpc32(VT_SYM, sym, pe->v);
     }
 }
diff --git a/tcc.h b/tcc.h
index ea4ae21a..130c1b95 100644
--- a/tcc.h
+++ b/tcc.h
@@ -521,6 +521,10 @@ struct TCCState {
     /* PE info */
     int pe_subsystem;
     unsigned long pe_file_align;
+    struct pe_uw {
+        Section *pdata;
+        int sym_1, sym_2, offs_1;
+    } pe_unwind;
 #endif
 
 #ifndef TCC_TARGET_PE
@@ -1167,6 +1171,9 @@ ST_FUNC int pe_output_file(TCCState * s1, const char *filename);
 ST_FUNC int pe_dllimport(int r, SValue *sv, void (*fn)(int r, SValue *sv));
 /* tiny_impdef.c */
 ST_FUNC char *get_export_names(FILE *fp);
+#ifdef TCC_TARGET_X86_64
+ST_FUNC void pe_add_unwind_data(unsigned start, unsigned end, unsigned stack);
+#endif
 #endif
 
 /* ------------ tccrun.c ----------------- */
diff --git a/tccpe.c b/tccpe.c
index 1b2724d6..be92129a 100644
--- a/tccpe.c
+++ b/tccpe.c
@@ -289,6 +289,7 @@ enum {
     sec_data ,
     sec_bss ,
     sec_idata ,
+    sec_pdata ,
     sec_other ,
     sec_rsrc ,
     sec_stab ,
@@ -301,6 +302,7 @@ static const DWORD pe_sec_flags[] = {
     0xC0000040, /* ".data"     , */
     0xC0000080, /* ".bss"      , */
     0x40000040, /* ".idata"    , */
+    0x40000040, /* ".pdata"    , */
     0xE0000060, /* < other >   , */
     0x40000040, /* ".rsrc"     , */
     0x42000802, /* ".stab"     , */
@@ -634,6 +636,10 @@ static int pe_write(struct pe_info *pe)
                 pe_set_datadir(&pe_header, IMAGE_DIRECTORY_ENTRY_RESOURCE, addr, size);
                 break;
 
+            case sec_pdata:
+                pe_set_datadir(&pe_header, IMAGE_DIRECTORY_ENTRY_EXCEPTION, addr, size);
+                break;
+
             case sec_stab:
                 break;
         }
@@ -1037,6 +1043,8 @@ static int pe_section_class(Section *s)
                 return sec_rsrc;
             if (0 == strcmp(name, ".iedat"))
                 return sec_idata;
+            if (0 == strcmp(name, ".pdata"))
+                return sec_pdata;
             return sec_other;
         } else if (type == SHT_NOBITS) {
             if (flags & SHF_WRITE)
@@ -1086,7 +1094,7 @@ static int pe_assign_addresses (struct pe_info *pe)
 #ifdef PE_MERGE_DATA
         if (c == sec_bss && pe->sec_count && si[-1].cls == sec_data) {
             /* append .bss to .data */
-            s->sh_addr = addr = ((addr-1) | 15) + 1;
+            s->sh_addr = addr = ((addr-1) | (s->sh_addralign-1)) + 1;
             addr += s->data_offset;
             si[-1].sh_size = addr - si[-1].sh_addr;
             continue;
@@ -1162,7 +1170,7 @@ static void pe_relocate_rva (struct pe_info *pe, Section *s)
                 ElfW(Sym) *sym = (ElfW(Sym) *)symtab_section->data + sym_index;
                 addr = sym->st_value;
             }
-            // printf("reloc rva %08x %08x\n", (DWORD)rel->r_offset, addr);
+            // printf("reloc rva %08x %08x %s\n", (DWORD)rel->r_offset, addr, s->name);
             *(DWORD*)(s->data + rel->r_offset) += addr - pe->imagebase;
         }
     }
@@ -1625,6 +1633,56 @@ ST_FUNC int pe_dllimport(int r, SValue *sv, void (*fn)(int r, SValue *sv))
 
 /* ------------------------------------------------------------- */
 #ifdef TCC_TARGET_X86_64
+ST_FUNC void pe_add_unwind_data(unsigned start, unsigned end, unsigned stack)
+{
+    static const char uw_info[] = {
+        0x01, // UBYTE: 3 Version , UBYTE: 5 Flags
+        0x04, // UBYTE Size of prolog
+        0x02, // UBYTE Count of unwind codes
+        0x05, // UBYTE: 4 Frame Register (rbp), UBYTE: 4 Frame Register offset (scaled)
+        // USHORT * n Unwind codes array
+        // 0x0b, 0x01, 0xff, 0xff, // stack size
+        0x04, 0x03, // set frame ptr (mov rsp -> rbp)
+        0x01, 0x50  // push reg (rbp)
+    };
+
+    struct pe_uw *pe_uw = &tcc_state->pe_unwind;
+
+    Section *uw, *pd;
+    WORD *p1;
+    DWORD *p2;
+    unsigned o2;
+
+    uw = data_section;
+    pd = pe_uw->pdata;
+    if (NULL == pd)
+    {
+        pe_uw->pdata = pd = find_section(tcc_state, ".pdata");
+        pe_uw->pdata->sh_addralign = 4;
+        section_ptr_add(uw, -uw->data_offset & 3);
+        pe_uw->offs_1 = uw->data_offset;
+        p1 = section_ptr_add(uw, sizeof uw_info);
+        /* use one common entry for all functions */
+        memcpy(p1, uw_info, sizeof uw_info);
+        pe_uw->sym_1 = put_elf_sym(symtab_section, 0, 0, 0, 0, text_section->sh_num, NULL);
+        pe_uw->sym_2 = put_elf_sym(symtab_section, 0, 0, 0, 0, uw->sh_num, NULL);
+    }
+
+    o2 = pd->data_offset;
+    p2 = section_ptr_add(pd, 3 * sizeof (DWORD));
+    /* record this function */
+    p2[0] = start;
+    p2[1] = end;
+    p2[2] = pe_uw->offs_1;
+    /* put relocations on it */
+    put_elf_reloc(symtab_section, pd, o2,   R_X86_64_RELATIVE, pe_uw->sym_1);
+    put_elf_reloc(symtab_section, pd, o2+4, R_X86_64_RELATIVE, pe_uw->sym_1);
+    put_elf_reloc(symtab_section, pd, o2+8, R_X86_64_RELATIVE, pe_uw->sym_2);
+}
+#endif
+
+/* ------------------------------------------------------------- */
+#ifdef TCC_TARGET_X86_64
 #define PE_STDSYM(n,s) n
 #else
 #define PE_STDSYM(n,s) "_" n s
diff --git a/tccrun.c b/tccrun.c
index e88f87e4..52855a78 100644
--- a/tccrun.c
+++ b/tccrun.c
@@ -78,6 +78,13 @@ int tcc_run(TCCState *s1, int argc, char **argv)
         return ret;
     }
 #endif
+
+#ifdef TCC_TARGET_PE
+    {
+      unsigned char *p = tcc_get_symbol(s1, "tinyc_no_getbp");
+      if (p) *p = 0;
+    }
+#endif
     return (*prog_main)(argc, argv);
 }
 
diff --git a/win32/include/_mingw.h b/win32/include/_mingw.h
index bbac35e2..baa454b2 100644
--- a/win32/include/_mingw.h
+++ b/win32/include/_mingw.h
@@ -58,7 +58,7 @@ typedef unsigned __int64 uintptr_t;
 #define _AMD64_ 1
 #define __x86_64 1
 #define USE_MINGW_SETJMP_TWO_ARGS
-#define mingw_getsp tinyc_getsp
+#define mingw_getsp tinyc_getbp
 #else
 typedef __int32 intptr_t;
 typedef unsigned __int32 uintptr_t;
diff --git a/win32/lib/chkstk.S b/win32/lib/chkstk.S
index 90a6f0dc..a757b161 100644
--- a/win32/lib/chkstk.S
+++ b/win32/lib/chkstk.S
@@ -57,11 +57,19 @@ P0:
     jmp     *8(%rax)
 
 /* ---------------------------------------------- */
-/* avoid msvcrt unwind stuff for setjmp/longjmp */
+/* setjmp/longjmp support */
 
-.globl tinyc_getsp
-tinyc_getsp:
+.globl tinyc_no_getbp
+tinyc_no_getbp:
+    .byte 0x90
+
+.globl tinyc_getbp
+tinyc_getbp:
     xor %rax,%rax
+    cmp %al,tinyc_no_getbp(%rax)
+    je t1
+    mov %rbp,%rax
+t1:
     ret
 
 /* ---------------------------------------------- */
diff --git a/x86_64-gen.c b/x86_64-gen.c
index d9f7528f..2e7c8beb 100644
--- a/x86_64-gen.c
+++ b/x86_64-gen.c
@@ -527,16 +527,6 @@ void store(int r, SValue *v)
     }
 }
 
-static void gadd_sp(int val)
-{
-    if (val == (char)val) {
-        o(0xc48348);
-        g(val);
-    } else {
-        oad(0xc48148, val); /* add $xxx, %rsp */
-    }
-}
-
 /* 'is_jmp' is '1' if it is a jump */
 static void gcall_or_jmp(int is_jmp)
 {
@@ -564,16 +554,238 @@ static void gcall_or_jmp(int is_jmp)
 }
 
 #ifdef TCC_TARGET_PE
+
 #define REGN 4
 static const uint8_t arg_regs[] = {
     TREG_RCX, TREG_RDX, TREG_R8, TREG_R9
 };
+
+static int func_scratch;
+
+/* Generate function call. The function address is pushed first, then
+   all the parameters in call order. This functions pops all the
+   parameters and the function address. */
+
+void gen_offs_sp(int b, int r, int d)
+{
+    if (d == (char)d) {
+        o(b | 0x4000 | (r << 11));
+        g(d);
+    } else {
+        o(b | 0x8000 | (r << 11));
+        gen_le32(d);
+    }
+}
+
+void gfunc_call(int nb_args)
+{
+    int size, align, r, args_size, i, d, j, bt;
+    int nb_reg_args, gen_reg;
+
+    /* calculate the number of integer/float arguments */
+    nb_reg_args = 0;
+    for(i = 0; i < nb_args; i++) {
+        bt = (vtop[-i].type.t & VT_BTYPE);
+        if (bt != VT_STRUCT && bt != VT_LDOUBLE)
+            nb_reg_args++;
+    }
+
+    args_size = (nb_reg_args < REGN ? REGN : nb_reg_args) * PTR_SIZE;
+    save_regs(0); /* save used temporary registers */
+
+    /* for struct arguments, we need to call memcpy and the function
+       call breaks register passing arguments we are preparing.
+       So, we process arguments which will be passed by stack first. */
+    for(i = 0; i < nb_args; i++) {
+        SValue *sv = &vtop[-i];
+        bt = (sv->type.t & VT_BTYPE);
+        if (bt == VT_STRUCT) {
+            size = type_size(&sv->type, &align);
+            /* align to stack align size */
+            size = (size + 15) & ~16;
+            /* generate structure store */
+            r = get_reg(RC_INT);
+            o(0x48);
+            gen_offs_sp(0x24048d, r, args_size);
+            args_size += size;
+
+            /* generate memcpy call */
+            vset(&sv->type, r | VT_LVAL, 0);
+            *++vtop = *sv;
+            vstore();
+            --vtop;
+
+        } else if (bt == VT_LDOUBLE) {
+
+            gv(RC_ST0);
+            gen_offs_sp(0x243cdb, 0, args_size);
+            args_size += 16;
+
+        }
+    }
+
+    if (func_scratch < args_size)
+        func_scratch = args_size;
+
+    gen_reg = nb_reg_args;
+    for(i = 0; i < nb_args; i++) {
+        bt = (vtop->type.t & VT_BTYPE);
+        if (bt == VT_STRUCT || bt == VT_LDOUBLE) {
+            ; /* done */
+
+        } else if (is_sse_float(vtop->type.t)) {
+            gv(RC_FLOAT); /* only one float register */
+            j = --gen_reg;
+            if (j >= REGN) {
+                o(0x0f66),
+                /* movq %xmm0, j*8(%rsp) */
+                gen_offs_sp(0x2444d6, 0, j*8);
+            } else {
+                d = arg_regs[j];
+                /* movaps %xmm0, %xmmN */
+                o(0x280f);
+                o(0xc0 + (j << 3));
+                /* mov %xmm0, %rxx */
+                o(0x66);
+                o(0x7e0f48 + (d >= 8));
+                o(0xc0 + (d & 7));
+            }
+        } else {
+            r = gv(RC_INT);
+            j = --gen_reg;
+            if (j >= REGN) {
+                o(0x48);
+                gen_offs_sp(0x244489, r, j*8);
+            } else {
+                d = arg_regs[j];
+                if (d != r) {
+                    o(0x8948 + (d >= 8));
+                    o(0xc0 + r*8 + (d & 7));
+                }
+            }
+        }
+        vtop--;
+    }
+    gcall_or_jmp(0);
+    vtop--;
+}
+
+
+#define FUNC_PROLOG_SIZE 11
+
+/* generate function prolog of type 't' */
+void gfunc_prolog(CType *func_type)
+{
+    int addr, align, size, reg_param_index, bt;
+    Sym *sym;
+    CType *type;
+
+    func_ret_sub = 0;
+    func_scratch = 0;
+    loc = 0;
+
+    addr = PTR_SIZE * 2;
+    ind += FUNC_PROLOG_SIZE;
+    func_sub_sp_offset = ind;
+    reg_param_index = 0;
+
+    sym = func_type->ref;
+
+    /* if the function returns a structure, then add an
+       implicit pointer parameter */
+    func_vt = sym->type;
+    if ((func_vt.t & VT_BTYPE) == VT_STRUCT) {
+        gen_modrm64(0x89, arg_regs[reg_param_index], VT_LOCAL, NULL, addr);
+        reg_param_index++;
+        addr += PTR_SIZE;
+    }
+
+    /* define parameters */
+    while ((sym = sym->next) != NULL) {
+        type = &sym->type;
+        bt = type->t & VT_BTYPE;
+        if (bt == VT_STRUCT || bt == VT_LDOUBLE)
+            continue;
+        if (reg_param_index < REGN) {
+            /* save arguments passed by register */
+            gen_modrm64(0x89, arg_regs[reg_param_index], VT_LOCAL, NULL, addr);
+        }
+        sym_push(sym->v & ~SYM_FIELD, type, VT_LOCAL | VT_LVAL, addr);
+        reg_param_index++;
+        addr += PTR_SIZE;
+    }
+
+    while (reg_param_index < REGN) {
+        if (func_type->ref->c == FUNC_ELLIPSIS)
+            gen_modrm64(0x89, arg_regs[reg_param_index], VT_LOCAL, NULL, addr);
+        reg_param_index++;
+        addr += PTR_SIZE;
+    }
+
+    sym = func_type->ref;
+    while ((sym = sym->next) != NULL) {
+        type = &sym->type;
+        bt = type->t & VT_BTYPE;
+        if (bt == VT_STRUCT || bt == VT_LDOUBLE) {
+            size = type_size(type, &align);
+            size = (size + 15) & -16;
+            sym_push(sym->v & ~SYM_FIELD, type, VT_LOCAL | VT_LVAL, addr);
+            addr += size;
+        }
+    }
+}
+
+/* generate function epilog */
+void gfunc_epilog(void)
+{
+    int v, saved_ind;
+
+    o(0xc9); /* leave */
+    if (func_ret_sub == 0) {
+        o(0xc3); /* ret */
+    } else {
+        o(0xc2); /* ret n */
+        g(func_ret_sub);
+        g(func_ret_sub >> 8);
+    }
+
+    saved_ind = ind;
+    ind = func_sub_sp_offset - FUNC_PROLOG_SIZE;
+    /* align local size to word & save local variables */
+    v = (func_scratch + -loc + 15) & -16;
+
+    pe_add_unwind_data(ind, saved_ind, v);
+
+    if (v >= 4096) {
+        Sym *sym = external_global_sym(TOK___chkstk, &func_old_type, 0);
+        oad(0xb8, v); /* mov stacksize, %eax */
+        oad(0xe8, -4); /* call __chkstk, (does the stackframe too) */
+        greloc(cur_text_section, sym, ind-4, R_X86_64_PC32);
+        o(0x90); /* fill for FUNC_PROLOG_SIZE = 11 bytes */
+    } else {
+        o(0xe5894855);  /* push %rbp, mov %rsp, %rbp */
+        o(0xec8148);  /* sub rsp, stacksize */
+        gen_le32(v);
+    }
+    ind = saved_ind;
+}
+
 #else
+
+static void gadd_sp(int val)
+{
+    if (val == (char)val) {
+        o(0xc48348);
+        g(val);
+    } else {
+        oad(0xc48148, val); /* add $xxx, %rsp */
+    }
+}
+
 #define REGN 6
 static const uint8_t arg_regs[REGN] = {
     TREG_RDI, TREG_RSI, TREG_RDX, TREG_RCX, TREG_R8, TREG_R9
 };
-#endif
 
 /* Generate function call. The function address is pushed first, then
    all the parameters in call order. This functions pops all the
@@ -593,11 +805,9 @@ void gfunc_call(int nb_args)
             args_size += type_size(&vtop->type, &align);
         } else if ((vtop[-i].type.t & VT_BTYPE) == VT_LDOUBLE) {
             args_size += 16;
-#ifndef TCC_TARGET_PE
         } else if (is_sse_float(vtop[-i].type.t)) {
             nb_sse_args++;
             if (nb_sse_args > 8) args_size += 8;
-#endif
         } else {
             nb_reg_args++;
             if (nb_reg_args > REGN) args_size += 8;
@@ -611,10 +821,6 @@ void gfunc_call(int nb_args)
     gen_reg = nb_reg_args;
     sse_reg = nb_sse_args;
 
-#ifdef TCC_TARGET_PE
-    save_regs(0); /* save used temporary registers */
-#endif
-
     /* adjust stack to align SSE boundary */
     if (args_size &= 8) {
         o(0x50); /* push $rax */
@@ -650,13 +856,8 @@ void gfunc_call(int nb_args)
             g(0x00);
             args_size += size;
         } else if (is_sse_float(vtop->type.t)) {
-#ifdef TCC_TARGET_PE
-            int j = --gen_reg;
-            if (j >= REGN) {
-#else
             int j = --sse_reg;
             if (j >= 8) {
-#endif
                 gv(RC_FLOAT);
                 o(0x50); /* push $rax */
                 /* movq %xmm0, (%rsp) */
@@ -688,42 +889,6 @@ void gfunc_call(int nb_args)
         if ((vtop->type.t & VT_BTYPE) == VT_STRUCT ||
             (vtop->type.t & VT_BTYPE) == VT_LDOUBLE) {
         } else if (is_sse_float(vtop->type.t)) {
-#ifdef TCC_TARGET_PE
-            int j = --gen_reg;
-            if (j < REGN) {
-                int d = arg_regs[j];
-                gv(RC_FLOAT); /* only one float register */
-                /* movaps %xmm0, %xmmN */
-                o(0x280f);
-                o(0xc0 + (j << 3));
-                o(0x50);
-                o(0xd60f66); /* movq %xmm0, (%rsp) */
-                o(0x2404 + (j << 3));
-                if (d < 8) {
-                    o(0x58 + d); /* pop d */
-                } else {
-                    o(0x58);
-                    o(0xc08949 + d - 8);
-                }
-            }
-        } else {
-            int j = --gen_reg;
-            /* simple type */
-            /* XXX: implicit cast ? */
-            if (j < REGN) {
-                int d = arg_regs[j];
-                r = gv(RC_INT);
-                if (d != r) {
-                    if (d < 8) {
-                        o(0x8948); /* mov */
-                        o(0xc0 + r * 8 + d);
-                    } else {
-                        o(0x8949); /* mov */
-                        o(0xc0 + r * 8 + d - 8);
-                    }
-                }
-            }
-#else
             int j = --sse_reg;
             if (j < 8) {
                 gv(RC_FLOAT); /* only one float register */
@@ -750,16 +915,10 @@ void gfunc_call(int nb_args)
                     o(0xc0 + r * 8 + j - 4);
                 }
             }
-#endif
         }
         vtop--;
     }
 
-#ifdef TCC_TARGET_PE
-    /* allocate scratch space */
-    gadd_sp(-8*REGN);
-    args_size += 8*REGN;
-#else
     save_regs(0); /* save used temporary registers */
 
     /* Copy R10 and R11 into RDX and RCX, respectively */
@@ -771,13 +930,13 @@ void gfunc_call(int nb_args)
     }
 
     oad(0xb8, nb_sse_args < 8 ? nb_sse_args : 8); /* mov nb_sse_args, %eax */
-#endif
     gcall_or_jmp(0);
     if (args_size)
         gadd_sp(args_size);
     vtop--;
 }
 
+
 #define FUNC_PROLOG_SIZE 11
 
 static void push_arg_reg(int i) {
@@ -793,15 +952,13 @@ void gfunc_prolog(CType *func_type)
     Sym *sym;
     CType *type;
 
-    func_ret_sub = 0;
-
     sym = func_type->ref;
     addr = PTR_SIZE * 2;
     loc = 0;
     ind += FUNC_PROLOG_SIZE;
     func_sub_sp_offset = ind;
+    func_ret_sub = 0;
 
-#ifndef TCC_TARGET_PE
     if (func_type->ref->c == FUNC_ELLIPSIS) {
         int seen_reg_num, seen_sse_num, seen_stack_size;
         seen_reg_num = seen_sse_num = 0;
@@ -857,7 +1014,6 @@ void gfunc_prolog(CType *func_type)
             push_arg_reg(REGN-1-i);
         }
     }
-#endif
 
     sym = func_type->ref;
     param_index = 0;
@@ -880,7 +1036,6 @@ void gfunc_prolog(CType *func_type)
         type = &sym->type;
         size = type_size(type, &align);
         size = (size + 3) & ~3;
-#ifndef TCC_TARGET_PE
         if (is_sse_float(type->t)) {
             if (sse_param_index < 8) {
                 /* save arguments passed by register */
@@ -893,21 +1048,12 @@ void gfunc_prolog(CType *func_type)
                 addr += size;
             }
             sse_param_index++;
-        } else
-#endif
-        if ((type->t & VT_BTYPE) == VT_STRUCT ||
+
+        } else if ((type->t & VT_BTYPE) == VT_STRUCT ||
                    (type->t & VT_BTYPE) == VT_LDOUBLE) {
             param_addr = addr;
             addr += size;
         } else {
-#ifdef TCC_TARGET_PE
-            if (reg_param_index < REGN) {
-                /* save arguments passed by register */
-                gen_modrm64(0x89, arg_regs[reg_param_index], VT_LOCAL, NULL, addr);
-            }
-            param_addr = addr;
-            addr += 8;
-#else
             if (reg_param_index < REGN) {
                 /* save arguments passed by register */
                 push_arg_reg(reg_param_index);
@@ -916,21 +1062,12 @@ void gfunc_prolog(CType *func_type)
                 param_addr = addr;
                 addr += 8;
             }
-#endif
             reg_param_index++;
         }
         sym_push(sym->v & ~SYM_FIELD, type,
                  VT_LOCAL | VT_LVAL, param_addr);
         param_index++;
     }
-#ifdef TCC_TARGET_PE
-    if (func_type->ref->c == FUNC_ELLIPSIS) {
-        for (i = reg_param_index; i < REGN; ++i) {
-            gen_modrm64(0x89, arg_regs[i], VT_LOCAL, NULL, addr);
-            addr += 8;
-        }
-    }
-#endif
 }
 
 /* generate function epilog */
@@ -950,23 +1087,14 @@ void gfunc_epilog(void)
     v = (-loc + 15) & -16;
     saved_ind = ind;
     ind = func_sub_sp_offset - FUNC_PROLOG_SIZE;
-#ifdef TCC_TARGET_PE
-    if (v >= 4096) {
-        Sym *sym = external_global_sym(TOK___chkstk, &func_old_type, 0);
-        oad(0xb8, v); /* mov stacksize, %eax */
-        oad(0xe8, -4); /* call __chkstk, (does the stackframe too) */
-        greloc(cur_text_section, sym, ind-4, R_X86_64_PC32);
-	o(0x90); /* fill for FUNC_PROLOG_SIZE = 11 bytes */
-    } else
-#endif
-    {
-        o(0xe5894855);  /* push %rbp, mov %rsp, %rbp */
-        o(0xec8148);  /* sub rsp, stacksize */
-        gen_le32(v);
-    }
+    o(0xe5894855);  /* push %rbp, mov %rsp, %rbp */
+    o(0xec8148);  /* sub rsp, stacksize */
+    gen_le32(v);
     ind = saved_ind;
 }
 
+#endif /* not PE */
+
 /* generate a jump to a label */
 int gjmp(int t)
 {
-- 
2.11.4.GIT