diff options
Diffstat (limited to 'libavutil')
| -rw-r--r-- | libavutil/x86/x86inc.asm | 62 |
1 files changed, 40 insertions, 22 deletions
diff --git a/libavutil/x86/x86inc.asm b/libavutil/x86/x86inc.asm index 4c0a4bdb1b..ae6813a2b4 100644 --- a/libavutil/x86/x86inc.asm +++ b/libavutil/x86/x86inc.asm @@ -42,6 +42,17 @@ %define public_prefix private_prefix %endif +%if HAVE_ALIGNED_STACK + %define STACK_ALIGNMENT 16 +%endif +%ifndef STACK_ALIGNMENT + %if ARCH_X86_64 + %define STACK_ALIGNMENT 16 + %else + %define STACK_ALIGNMENT 4 + %endif +%endif + %define WIN64 0 %define UNIX64 0 %if ARCH_X86_64 @@ -108,8 +119,9 @@ ; %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 = (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), +; %4 = (optional) stack size to be allocated. The stack will be aligned before +; allocating the specified stack size. If the required stack alignment is +; larger than the known stack alignment the stack will be manually aligned ; 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. @@ -117,8 +129,10 @@ ; PROLOGUE can also be invoked by adding the same options to cglobal ; e.g. -; cglobal foo, 2,3,0, dst, src, tmp -; declares a function (foo), taking two args (dst and src) and one local variable (tmp) +; cglobal foo, 2,3,7,0x40, dst, src, tmp +; declares a function (foo) that automatically loads two arguments (dst and +; src) into registers, uses one additional register (tmp) plus 7 vector +; registers (m0-m6) and allocates 0x40 bytes of stack space. ; TODO Some functions can use some args directly from the stack. If they're the ; last args then you can just not declare them, but if they're in the middle @@ -319,26 +333,28 @@ 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 +%define required_stack_alignment ((mmsize + 15) & ~15) + %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 %%pad 0 %assign stack_size %1 %if stack_size < 0 %assign stack_size -stack_size %endif - %assign stack_size_padded stack_size %if WIN64 - %assign stack_size_padded stack_size_padded + 32 ; reserve 32 bytes for shadow space + %assign %%pad %%pad + 32 ; shadow space %if mmsize != 8 %assign xmm_regs_used %2 %if xmm_regs_used > 8 - %assign stack_size_padded stack_size_padded + (xmm_regs_used-8)*16 + %assign %%pad %%pad + (xmm_regs_used-8)*16 ; callee-saved xmm registers %endif %endif %endif - %if mmsize <= 16 && HAVE_ALIGNED_STACK - %assign stack_size_padded stack_size_padded + %%stack_alignment - gprsize - (stack_offset & (%%stack_alignment - 1)) + %if required_stack_alignment <= STACK_ALIGNMENT + ; maintain the current stack alignment + %assign stack_size_padded stack_size + %%pad + ((-%%pad-stack_offset-gprsize) & (STACK_ALIGNMENT-1)) SUB rsp, stack_size_padded %else %assign %%reg_num (regs_used - 1) @@ -347,17 +363,17 @@ DECLARE_REG_TMP_SIZE 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14 ; 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 %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 + %xdefine rstkm [rsp + stack_size + %%pad] + %assign %%pad %%pad + gprsize %else ; can keep rsp in rstk during whole function - sub rsp, stack_size_padded - and rsp, ~(%%stack_alignment-1) %xdefine rstkm rstk %endif + %assign stack_size_padded stack_size + ((%%pad + required_stack_alignment-1) & ~(required_stack_alignment-1)) + mov rstk, rsp + and rsp, ~(required_stack_alignment-1) + sub rsp, stack_size_padded + movifnidn rstkm, rstk %endif WIN64_PUSH_XMM %endif @@ -366,7 +382,7 @@ DECLARE_REG_TMP_SIZE 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14 %macro SETUP_STACK_POINTER 1 %ifnum %1 - %if %1 != 0 && (HAVE_ALIGNED_STACK == 0 || mmsize == 32) + %if %1 != 0 && required_stack_alignment > STACK_ALIGNMENT %if %1 > 0 %assign regs_used (regs_used + 1) %elif ARCH_X86_64 && regs_used == num_args && num_args <= 4 + UNIX64 * 2 @@ -440,7 +456,9 @@ DECLARE_REG 14, R15, 120 %assign xmm_regs_used %1 ASSERT xmm_regs_used <= 16 %if xmm_regs_used > 8 - %assign stack_size_padded (xmm_regs_used-8)*16 + (~stack_offset&8) + 32 + ; Allocate stack space for callee-saved xmm registers plus shadow space and align the stack. + %assign %%pad (xmm_regs_used-8)*16 + 32 + %assign stack_size_padded %%pad + ((-%%pad-stack_offset-gprsize) & (STACK_ALIGNMENT-1)) SUB rsp, stack_size_padded %endif WIN64_PUSH_XMM @@ -456,7 +474,7 @@ DECLARE_REG 14, R15, 120 %endrep %endif %if stack_size_padded > 0 - %if stack_size > 0 && (mmsize == 32 || HAVE_ALIGNED_STACK == 0) + %if stack_size > 0 && required_stack_alignment > STACK_ALIGNMENT mov rsp, rstkm %else add %1, stack_size_padded @@ -522,7 +540,7 @@ DECLARE_REG 14, R15, 72 %macro RET 0 %if stack_size_padded > 0 -%if mmsize == 32 || HAVE_ALIGNED_STACK == 0 +%if required_stack_alignment > STACK_ALIGNMENT mov rsp, rstkm %else add rsp, stack_size_padded @@ -578,7 +596,7 @@ DECLARE_ARG 7, 8, 9, 10, 11, 12, 13, 14 %macro RET 0 %if stack_size_padded > 0 -%if mmsize == 32 || HAVE_ALIGNED_STACK == 0 +%if required_stack_alignment > STACK_ALIGNMENT mov rsp, rstkm %else add rsp, stack_size_padded |