x86inc: support stack mem allocation and re-alignment in PROLOGUE

Use this in 8-bit loopfilter functions so they can be used if
there is no aligned stack (e.g. x86-32 MSVC or ICC 10.x).

diff --git a/common/deblock.c b/common/deblock.c
index 1f05e831cc7eb948005b0ec3f9bb92a87444fc92..fd840dc261acb086240e5197554aeaf262b59f07 100644 (file)
--- a/common/deblock.c
+++ b/common/deblock.c
@@ -779,13 +779,13 @@ void x264_deblock_init( int cpu, x264_deblock_function_t *pf, int b_mbaff )
             pf->deblock_h_chroma_422 = x264_deblock_h_chroma_422_sse2;
             pf->deblock_h_chroma_422_intra = x264_deblock_h_chroma_422_intra_sse2;
             pf->deblock_chroma_420_mbaff = x264_deblock_h_chroma_mbaff_sse2;
+            pf->deblock_luma[1] = x264_deblock_v_luma_sse2;
+            pf->deblock_luma[0] = x264_deblock_h_luma_sse2;
+            pf->deblock_luma_intra[1] = x264_deblock_v_luma_intra_sse2;
+            pf->deblock_luma_intra[0] = x264_deblock_h_luma_intra_sse2;
             if( !(cpu&X264_CPU_STACK_MOD4) )
             {
-                pf->deblock_luma[1] = x264_deblock_v_luma_sse2;
-                pf->deblock_luma[0] = x264_deblock_h_luma_sse2;
                 pf->deblock_chroma[1] = x264_deblock_v_chroma_sse2;
-                pf->deblock_luma_intra[1] = x264_deblock_v_luma_intra_sse2;
-                pf->deblock_luma_intra[0] = x264_deblock_h_luma_intra_sse2;
                 pf->deblock_chroma_intra[1] = x264_deblock_v_chroma_intra_sse2;
                 pf->deblock_h_chroma_420_intra = x264_deblock_h_chroma_intra_sse2;
 #if HIGH_BIT_DEPTH
@@ -801,13 +801,13 @@ void x264_deblock_init( int cpu, x264_deblock_function_t *pf, int b_mbaff )
             pf->deblock_h_chroma_420 = x264_deblock_h_chroma_avx;
             pf->deblock_h_chroma_422 = x264_deblock_h_chroma_422_avx;
             pf->deblock_h_chroma_422_intra = x264_deblock_h_chroma_422_intra_avx;
+            pf->deblock_luma[1] = x264_deblock_v_luma_avx;
+            pf->deblock_luma[0] = x264_deblock_h_luma_avx;
+            pf->deblock_luma_intra[1] = x264_deblock_v_luma_intra_avx;
+            pf->deblock_luma_intra[0] = x264_deblock_h_luma_intra_avx;
             if( !(cpu&X264_CPU_STACK_MOD4) )
             {
-                pf->deblock_luma[1] = x264_deblock_v_luma_avx;
-                pf->deblock_luma[0] = x264_deblock_h_luma_avx;
                 pf->deblock_chroma[1] = x264_deblock_v_chroma_avx;
-                pf->deblock_luma_intra[1] = x264_deblock_v_luma_intra_avx;
-                pf->deblock_luma_intra[0] = x264_deblock_h_luma_intra_avx;
                 pf->deblock_chroma_intra[1] = x264_deblock_v_chroma_intra_avx;
                 pf->deblock_h_chroma_420_intra = x264_deblock_h_chroma_intra_avx;
 #if HIGH_BIT_DEPTH

diff --git a/common/x86/deblock-a.asm b/common/x86/deblock-a.asm
index b4cfa4a441a4d3e41206944b29a7b7b075af57c5..210761a85f9328aa324bdb56d591cd33bdaf436f 100644 (file)
--- a/common/x86/deblock-a.asm
+++ b/common/x86/deblock-a.asm
@@ -1205,14 +1205,12 @@ DEBLOCK_LUMA
 ;-----------------------------------------------------------------------------
 ; void deblock_v8_luma( uint8_t *pix, intptr_t stride, int alpha, int beta, int8_t *tc0 )
 ;-----------------------------------------------------------------------------
-cglobal deblock_%1_luma, 5,5
+cglobal deblock_%1_luma, 5,5,8,2*%2
     lea     r4, [r1*3]
     dec     r2     ; alpha-1
     neg     r4
     dec     r3     ; beta-1
     add     r4, r0 ; pix-3*stride
-    %assign pad 2*%2+12-(stack_offset&15)
-    SUB     esp, pad
 
     mova    m0, [r4+r1]   ; p1
     mova    m1, [r4+2*r1] ; p0
@@ -1251,22 +1249,19 @@ cglobal deblock_%1_luma, 5,5
     DEBLOCK_P0_Q0
     mova    [r4+2*r1], m1
     mova    [r0], m2
-    ADD     esp, pad
     RET
 
 ;-----------------------------------------------------------------------------
 ; void deblock_h_luma( uint8_t *pix, intptr_t stride, int alpha, int beta, int8_t *tc0 )
 ;-----------------------------------------------------------------------------
 INIT_MMX cpuname
-cglobal deblock_h_luma, 0,5
+cglobal deblock_h_luma, 0,5,8,0x60+HAVE_ALIGNED_STACK*12
     mov    r0, r0mp
     mov    r3, r1m
     lea    r4, [r3*3]
     sub    r0, 4
     lea    r1, [r0+r4]
-    %assign pad 0x78-(stack_offset&15)
-    SUB    esp, pad
-%define pix_tmp esp+12
+    %define pix_tmp esp+12*HAVE_ALIGNED_STACK
 
     ; transpose 6x16 -> tmp space
     TRANSPOSE6x8_MEM  PASS8ROWS(r0, r1, r3, r4), pix_tmp
@@ -1308,7 +1303,6 @@ cglobal deblock_h_luma, 0,5
     movq   m3, [pix_tmp+0x48]
     TRANSPOSE8x4B_STORE  PASS8ROWS(r0, r1, r3, r4)
 
-    ADD    esp, pad
     RET
 %endmacro ; DEBLOCK_LUMA
 
@@ -1439,7 +1433,7 @@ DEBLOCK_LUMA v, 16
     %define mpb_0 m14
     %define mpb_1 m15
 %else
-    %define spill(x) [esp+16*x+((stack_offset+4)&15)]
+    %define spill(x) [esp+16*x]
     %define p2 [r4+r1]
     %define q2 [r0+2*r1]
     %define t4 spill(0)
@@ -1454,10 +1448,7 @@ DEBLOCK_LUMA v, 16
 ;-----------------------------------------------------------------------------
 ; void deblock_v_luma_intra( uint8_t *pix, intptr_t stride, int alpha, int beta )
 ;-----------------------------------------------------------------------------
-cglobal deblock_%1_luma_intra, 4,6,16
-%if ARCH_X86_64 == 0
-    sub     esp, 0x60
-%endif
+cglobal deblock_%1_luma_intra, 4,6,16,ARCH_X86_64*0x50-0x50
     lea     r4, [r1*4]
     lea     r5, [r1*3] ; 3*stride
     dec     r2d        ; alpha-1
@@ -1506,9 +1497,6 @@ cglobal deblock_%1_luma_intra, 4,6,16
     LUMA_INTRA_SWAP_PQ
     LUMA_INTRA_P012 [r0], [r0+r1], [r0+2*r1], [r0+r5]
 .end:
-%if ARCH_X86_64 == 0
-    add     esp, 0x60
-%endif
     RET
 
 INIT_MMX cpuname
@@ -1545,12 +1533,10 @@ cglobal deblock_h_luma_intra, 4,9
     add   rsp, 0x88
     RET
 %else
-cglobal deblock_h_luma_intra, 2,4
+cglobal deblock_h_luma_intra, 2,4,8,0x80
     lea    r3,  [r1*3]
     sub    r0,  4
     lea    r2,  [r0+r3]
-%assign pad 0x8c-(stack_offset&15)
-    SUB    rsp, pad
     %define pix_tmp rsp
 
     ; transpose 8x16 -> tmp space
@@ -1581,7 +1567,6 @@ cglobal deblock_h_luma_intra, 2,4
     lea    r0,  [r0+r1*8]
     lea    r2,  [r2+r1*8]
     TRANSPOSE8x8_MEM  PASS8ROWS(pix_tmp+8, pix_tmp+0x38, 0x10, 0x30), PASS8ROWS(r0, r2, r1, r3)
-    ADD    rsp, pad
     RET
 %endif ; ARCH_X86_64
 %endmacro ; DEBLOCK_LUMA_INTRA

diff --git a/common/x86/x86inc.asm b/common/x86/x86inc.asm
index 23f6f5ff38f9212e4ccecba5170fa9978265a3b6..7888903ad8e89a597b5136f03a4af5a8bdc04a12 100644 (file)
--- a/common/x86/x86inc.asm
+++ b/common/x86/x86inc.asm
@@ -105,7 +105,12 @@ CPU amdnop
 ; %1 = number of arguments. loads them from stack if needed.
 ; %2 = number of registers used. pushes callee-saved regs if needed.
 ; %3 = number of xmm registers used. pushes callee-saved xmm regs if needed.
-; %4 = list of names to define to registers
+; %4 = (optional) stack size to be allocated. If not aligned (x86-32 ICC 10.x,
+;      MSVC or YMM), the stack will be manually aligned (to 16 or 32 bytes),
+;      and an extra register will be allocated to hold the original stack
+;      pointer (to not invalidate r0m etc.). To prevent the use of an extra
+;      register as stack pointer, request a negative stack size.
+; %4+/%5+ = list of names to define to registers
 ; PROLOGUE can also be invoked by adding the same options to cglobal
 
 ; e.g.
@@ -140,11 +145,11 @@ CPU amdnop
         %define r%1m  %2d
         %define r%1mp %2
     %elif ARCH_X86_64 ; memory
-        %define r%1m [rsp + stack_offset + %3]
-        %define r%1mp qword r %+ %1m
+        %define r%1m [rstk + stack_offset + %3]
+        %define r%1mp qword r %+ %1 %+ m
     %else
-        %define r%1m [esp + stack_offset + %3]
-        %define r%1mp dword r %+ %1m
+        %define r%1m [rstk + stack_offset + %3]
+        %define r%1mp dword r %+ %1 %+ m
     %endif
     %define r%1  %2
 %endmacro
@@ -205,12 +210,16 @@ DECLARE_REG_TMP_SIZE 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14
 
 %macro PUSH 1
     push %1
-    %assign stack_offset stack_offset+gprsize
+    %ifidn rstk, rsp
+        %assign stack_offset stack_offset+gprsize
+    %endif
 %endmacro
 
 %macro POP 1
     pop %1
-    %assign stack_offset stack_offset-gprsize
+    %ifidn rstk, rsp
+        %assign stack_offset stack_offset-gprsize
+    %endif
 %endmacro
 
 %macro PUSH_IF_USED 1-*
@@ -242,14 +251,14 @@ DECLARE_REG_TMP_SIZE 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14
 
 %macro SUB 2
     sub %1, %2
-    %ifidn %1, rsp
+    %ifidn %1, rstk
         %assign stack_offset stack_offset+(%2)
     %endif
 %endmacro
 
 %macro ADD 2
     add %1, %2
-    %ifidn %1, rsp
+    %ifidn %1, rstk
         %assign stack_offset stack_offset-(%2)
     %endif
 %endmacro
@@ -307,6 +316,79 @@ DECLARE_REG_TMP_SIZE 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14
     %assign n_arg_names %0
 %endmacro
 
+%macro ALLOC_STACK 1-2 0 ; stack_size, n_xmm_regs (for win64 only)
+    %ifnum %1
+        %if %1 != 0
+            %assign %%stack_alignment ((mmsize + 15) & ~15)
+            %assign stack_size %1
+            %if stack_size < 0
+                %assign stack_size -stack_size
+            %endif
+            %if mmsize != 8
+                %assign xmm_regs_used %2
+            %endif
+            %if mmsize <= 16 && HAVE_ALIGNED_STACK
+                %assign stack_size_padded stack_size + %%stack_alignment - gprsize - (stack_offset & (%%stack_alignment - 1))
+                %if xmm_regs_used > 6
+                    %assign stack_size_padded stack_size_padded + (xmm_regs_used - 6) * 16
+                %endif
+                SUB rsp, stack_size_padded
+            %else
+                %assign %%reg_num (regs_used - 1)
+                %xdefine rstk r %+ %%reg_num
+                ; align stack, and save original stack location directly above
+                ; it, i.e. in [rsp+stack_size_padded], so we can restore the
+                ; stack in a single instruction (i.e. mov rsp, rstk or mov
+                ; rsp, [rsp+stack_size_padded])
+                mov  rstk, rsp
+                %assign stack_size_padded stack_size
+                %if xmm_regs_used > 6
+                    %assign stack_size_padded stack_size_padded + (xmm_regs_used - 6) * 16
+                    %if mmsize == 32 && xmm_regs_used & 1
+                        ; re-align to 32 bytes
+                        %assign stack_size_padded (stack_size_padded + 16)
+                    %endif
+                %endif
+                %if %1 < 0 ; need to store rsp on stack
+                    sub  rsp, gprsize+stack_size_padded
+                    and  rsp, ~(%%stack_alignment-1)
+                    %xdefine rstkm [rsp+stack_size_padded]
+                    mov rstkm, rstk
+                %else ; can keep rsp in rstk during whole function
+                    sub  rsp, stack_size_padded
+                    and  rsp, ~(%%stack_alignment-1)
+                    %xdefine rstkm rstk
+                %endif
+            %endif
+            %if xmm_regs_used > 6
+                WIN64_PUSH_XMM
+            %endif
+        %endif
+    %endif
+%endmacro
+
+%macro SETUP_STACK_POINTER 1
+    %ifnum %1
+        %if %1 != 0 && (HAVE_ALIGNED_STACK == 0 || mmsize == 32)
+            %if %1 > 0
+                %assign regs_used (regs_used + 1)
+            %elif ARCH_X86_64 && regs_used == num_args && num_args <= 4 + UNIX64 * 2
+                %warning "Stack pointer will overwrite register argument"
+            %endif
+        %endif
+    %endif
+%endmacro
+
+%macro DEFINE_ARGS_INTERNAL 3+
+    %ifnum %2
+        DEFINE_ARGS %3
+    %elif %1 == 4
+        DEFINE_ARGS %2
+    %elif %1 > 4
+        DEFINE_ARGS %2, %3
+    %endif
+%endmacro
+
 %if WIN64 ; Windows x64 ;=================================================
 
 DECLARE_REG 0,  rcx
@@ -325,19 +407,27 @@ DECLARE_REG 12, R13, 104
 DECLARE_REG 13, R14, 112
 DECLARE_REG 14, R15, 120
 
-%macro PROLOGUE 2-4+ 0 ; #args, #regs, #xmm_regs, arg_names...
+%macro PROLOGUE 2-5+ 0 ; #args, #regs, #xmm_regs, [stack_size,] arg_names...
     %assign num_args %1
     %assign regs_used %2
     ASSERT regs_used >= num_args
+    SETUP_STACK_POINTER %4
     ASSERT regs_used <= 15
     PUSH_IF_USED 7, 8, 9, 10, 11, 12, 13, 14
-    %if mmsize == 8
-        %assign xmm_regs_used 0
-    %else
+    ALLOC_STACK %4, %3
+    %if mmsize != 8 && stack_size == 0
         WIN64_SPILL_XMM %3
     %endif
     LOAD_IF_USED 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14
-    DEFINE_ARGS %4
+    DEFINE_ARGS_INTERNAL %0, %4, %5
+%endmacro
+
+%macro WIN64_PUSH_XMM 0
+    %assign %%i xmm_regs_used
+    %rep (xmm_regs_used-6)
+        %assign %%i %%i-1
+        movdqa [rsp + (%%i-6)*16 + stack_size + (~stack_offset&8)], xmm %+ %%i
+    %endrep
 %endmacro
 
 %macro WIN64_SPILL_XMM 1
@@ -345,11 +435,7 @@ DECLARE_REG 14, R15, 120
     ASSERT xmm_regs_used <= 16
     %if xmm_regs_used > 6
         SUB rsp, (xmm_regs_used-6)*16+16
-        %assign %%i xmm_regs_used
-        %rep (xmm_regs_used-6)
-            %assign %%i %%i-1
-            movdqa [rsp + (%%i-6)*16+(~stack_offset&8)], xmm %+ %%i
-        %endrep
+        WIN64_PUSH_XMM
     %endif
 %endmacro
 
@@ -358,19 +444,28 @@ DECLARE_REG 14, R15, 120
         %assign %%i xmm_regs_used
         %rep (xmm_regs_used-6)
             %assign %%i %%i-1
-            movdqa xmm %+ %%i, [%1 + (%%i-6)*16+(~stack_offset&8)]
+            movdqa xmm %+ %%i, [%1 + (%%i-6)*16+stack_size+(~stack_offset&8)]
         %endrep
-        add %1, (xmm_regs_used-6)*16+16
+        %if stack_size_padded == 0
+            add %1, (xmm_regs_used-6)*16+16
+        %endif
+    %endif
+    %if stack_size_padded > 0
+        %if stack_size > 0 && (mmsize == 32 || HAVE_ALIGNED_STACK == 0)
+            mov rsp, rstkm
+        %else
+            add %1, stack_size_padded
+        %endif
     %endif
 %endmacro
 
 %macro WIN64_RESTORE_XMM 1
     WIN64_RESTORE_XMM_INTERNAL %1
-    %assign stack_offset stack_offset-(xmm_regs_used-6)*16+16
+    %assign stack_offset (stack_offset-stack_size_padded)
     %assign xmm_regs_used 0
 %endmacro
 
-%define has_epilogue regs_used > 7 || xmm_regs_used > 6 || mmsize == 32
+%define has_epilogue regs_used > 7 || xmm_regs_used > 6 || mmsize == 32 || stack_size > 0
 
 %macro RET 0
     WIN64_RESTORE_XMM_INTERNAL rsp
@@ -399,19 +494,28 @@ DECLARE_REG 12, R13, 56
 DECLARE_REG 13, R14, 64
 DECLARE_REG 14, R15, 72
 
-%macro PROLOGUE 2-4+ ; #args, #regs, #xmm_regs, arg_names...
+%macro PROLOGUE 2-5+ ; #args, #regs, #xmm_regs, [stack_size,] arg_names...
     %assign num_args %1
     %assign regs_used %2
     ASSERT regs_used >= num_args
+    SETUP_STACK_POINTER %4
     ASSERT regs_used <= 15
     PUSH_IF_USED 9, 10, 11, 12, 13, 14
+    ALLOC_STACK %4
     LOAD_IF_USED 6, 7, 8, 9, 10, 11, 12, 13, 14
-    DEFINE_ARGS %4
+    DEFINE_ARGS_INTERNAL %0, %4, %5
 %endmacro
 
-%define has_epilogue regs_used > 9 || mmsize == 32
+%define has_epilogue regs_used > 9 || mmsize == 32 || stack_size > 0
 
 %macro RET 0
+%if stack_size_padded > 0
+%if mmsize == 32 || HAVE_ALIGNED_STACK == 0
+    mov rsp, rstkm
+%else
+    add rsp, stack_size_padded
+%endif
+%endif
     POP_IF_USED 14, 13, 12, 11, 10, 9
 %if mmsize == 32
     vzeroupper
@@ -432,7 +536,7 @@ DECLARE_REG 6, ebp, 28
 
 %macro DECLARE_ARG 1-*
     %rep %0
-        %define r%1m [esp + stack_offset + 4*%1 + 4]
+        %define r%1m [rstk + stack_offset + 4*%1 + 4]
         %define r%1mp dword r%1m
         %rotate 1
     %endrep
@@ -440,21 +544,34 @@ DECLARE_REG 6, ebp, 28
 
 DECLARE_ARG 7, 8, 9, 10, 11, 12, 13, 14
 
-%macro PROLOGUE 2-4+ ; #args, #regs, #xmm_regs, arg_names...
+%macro PROLOGUE 2-5+ ; #args, #regs, #xmm_regs, [stack_size,] arg_names...
     %assign num_args %1
     %assign regs_used %2
+    ASSERT regs_used >= num_args
+    %if num_args > 7
+        %assign num_args 7
+    %endif
     %if regs_used > 7
         %assign regs_used 7
     %endif
-    ASSERT regs_used >= num_args
+    SETUP_STACK_POINTER %4
+    ASSERT regs_used <= 7
     PUSH_IF_USED 3, 4, 5, 6
+    ALLOC_STACK %4
     LOAD_IF_USED 0, 1, 2, 3, 4, 5, 6
-    DEFINE_ARGS %4
+    DEFINE_ARGS_INTERNAL %0, %4, %5
 %endmacro
 
-%define has_epilogue regs_used > 3 || mmsize == 32
+%define has_epilogue regs_used > 3 || mmsize == 32 || stack_size > 0
 
 %macro RET 0
+%if stack_size_padded > 0
+%if mmsize == 32 || HAVE_ALIGNED_STACK == 0
+    mov rsp, rstkm
+%else
+    add rsp, stack_size_padded
+%endif
+%endif
     POP_IF_USED 6, 5, 4, 3
 %if mmsize == 32
     vzeroupper
@@ -469,6 +586,8 @@ DECLARE_ARG 7, 8, 9, 10, 11, 12, 13, 14
 %endmacro
 %macro WIN64_RESTORE_XMM 1
 %endmacro
+%macro WIN64_PUSH_XMM 0
+%endmacro
 %endif
 
 %macro REP_RET 0
@@ -498,12 +617,10 @@ DECLARE_ARG 7, 8, 9, 10, 11, 12, 13, 14
 ; Applies any symbol mangling needed for C linkage, and sets up a define such that
 ; subsequent uses of the function name automatically refer to the mangled version.
 ; Appends cpuflags to the function name if cpuflags has been specified.
-%macro cglobal 1-2+ ; name, [PROLOGUE args]
-%if %0 == 1
-    cglobal_internal %1 %+ SUFFIX
-%else
+%macro cglobal 1-2+ "" ; name, [PROLOGUE args]
+    ; the "" is a workaround for nasm, which fails if SUFFIX is empty
+    ; and we call cglobal_internal with just %1 %+ SUFFIX (without %2)
     cglobal_internal %1 %+ SUFFIX, %2
-%endif
 %endmacro
 %macro cglobal_internal 1-2+
     %ifndef cglobaled_%1
@@ -520,8 +637,12 @@ DECLARE_ARG 7, 8, 9, 10, 11, 12, 13, 14
     align function_align
     %1:
     RESET_MM_PERMUTATION ; not really needed, but makes disassembly somewhat nicer
+    %xdefine rstk rsp
     %assign stack_offset 0
-    %if %0 > 1
+    %assign stack_size 0
+    %assign stack_size_padded 0
+    %assign xmm_regs_used 0
+    %ifnidn %2, ""
         PROLOGUE %2
     %endif
 %endmacro

diff --git a/configure b/configure
index 6b2d616c4a6bfc6239ba1686e6efe7d7bfd576da..94285b274f3087b3e47d39148f4c284cd819828e 100755 (executable)
--- a/configure
+++ b/configure
@@ -528,6 +528,7 @@ esac
 
 LDFLAGS="$LDFLAGS $libm"
 
+aligned_stack=1
 case $host_cpu in
     i*86)
         ARCH="X86"
@@ -548,6 +549,7 @@ case $host_cpu in
                 # < 11 is completely incapable of keeping a mod16 stack
                 if cpp_check "" "" "__INTEL_COMPILER < 1100" ; then
                     define BROKEN_STACK_ALIGNMENT
+                    aligned_stack=0
                 # 11 <= x < 12 is capable of keeping a mod16 stack, but defaults to not doing so.
                 elif cpp_check "" "" "__INTEL_COMPILER < 1200" ; then
                     CFLAGS="$CFLAGS -falign-stack=assume-16-byte"
@@ -555,7 +557,7 @@ case $host_cpu in
                 # >= 12 defaults to a mod16 stack
             fi
             # icl on windows has no mod16 stack support
-            [ $SYS = WINDOWS ] && define BROKEN_STACK_ALIGNMENT
+            [ $SYS = WINDOWS ] && define BROKEN_STACK_ALIGNMENT && aligned_stack=0
         fi
         if [ "$SYS" = MACOSX ]; then
             ASFLAGS="$ASFLAGS -f macho -DPREFIX"
@@ -648,6 +650,7 @@ case $host_cpu in
         ARCH="$(echo $host_cpu | tr a-z A-Z)"
         ;;
 esac
+ASFLAGS="$ASFLAGS -DHAVE_ALIGNED_STACK=${aligned_stack}"
 
 if [ $SYS = WINDOWS ]; then
     if ! rc_check "0 RCDATA {0}" ; then