in rts/StgCRun.c [367:547]
static void GNUC3_ATTRIBUTE(used)
StgRunIsImplementedInAssembler(void)
{
__asm__ volatile (
/*
* save callee-saves registers on behalf of the STG code.
*/
STG_GLOBAL STG_RUN "\n"
#if !defined(mingw32_HOST_OS)
STG_HIDDEN STG_RUN "\n"
#endif
STG_RUN ":\n\t"
"subq %1, %%rsp\n\t"
"movq %%rsp, %%rax\n\t"
"subq %0, %%rsp\n\t"
"movq %%rbx,0(%%rax)\n\t"
"movq %%rbp,8(%%rax)\n\t"
"movq %%r12,16(%%rax)\n\t"
"movq %%r13,24(%%rax)\n\t"
"movq %%r14,32(%%rax)\n\t"
"movq %%r15,40(%%rax)\n\t"
#if defined(mingw32_HOST_OS)
/*
* Additional callee saved registers on Win64. This must match
* callClobberedRegisters in compiler/nativeGen/X86/Regs.hs as
* both represent the Win64 calling convention.
*/
"movq %%rdi,48(%%rax)\n\t"
"movq %%rsi,56(%%rax)\n\t"
"movq %%xmm6, 64(%%rax)\n\t"
"movq %%xmm7, 72(%%rax)\n\t"
"movq %%xmm8, 80(%%rax)\n\t"
"movq %%xmm9, 88(%%rax)\n\t"
"movq %%xmm10, 96(%%rax)\n\t"
"movq %%xmm11,104(%%rax)\n\t"
"movq %%xmm12,112(%%rax)\n\t"
"movq %%xmm13,120(%%rax)\n\t"
"movq %%xmm14,128(%%rax)\n\t"
"movq %%xmm15,136(%%rax)\n\t"
#endif
#if !defined(darwin_HOST_OS)
/*
* Let the unwinder know where we saved the registers
* See Note [Unwinding foreign exports on x86-64].
*
* N.B. We don't support unwinding on Darwin due to
* various toolchain insanity.
*/
".cfi_def_cfa rsp, 0\n\t"
".cfi_offset rbx, %c2\n\t"
".cfi_offset rbp, %c3\n\t"
".cfi_offset r12, %c4\n\t"
".cfi_offset r13, %c5\n\t"
".cfi_offset r14, %c6\n\t"
".cfi_offset r15, %c7\n\t"
".cfi_offset rip, %c8\n\t"
".cfi_escape " // DW_CFA_val_expression is not expressible otherwise
"0x16, " // DW_CFA_val_expression
"0x07, " // register num 7 - rsp
"0x04, " // block length
"0x77, " // DW_OP_breg7 - signed LEB128 offset from rsp
#define RSP_DELTA (RESERVED_C_STACK_BYTES + STG_RUN_STACK_FRAME_SIZE + 8)
"%c9" // signed LEB128 encoded delta - byte 1
#if (RSP_DELTA >> 7) > 0
", %c10" // signed LEB128 encoded delta - byte 2
#endif
#if (RSP_DELTA >> 14) > 0
", %c11" // signed LEB128 encoded delta - byte 3
#endif
#if (RSP_DELTA >> 21) > 0
", %c12" // signed LEB128 encoded delta - byte 4
#endif
#if (RSP_DELTA >> 28) > 0
#error "RSP_DELTA too big"
#endif
"\n\t"
#endif /* !defined(darwin_HOST_OS) */
/*
* Set BaseReg
*/
#if defined(mingw32_HOST_OS)
"movq %%rdx,%%r13\n\t"
#else
"movq %%rsi,%%r13\n\t"
#endif
/*
* grab the function argument from the stack, and jump to it.
*/
#if defined(mingw32_HOST_OS)
"movq %%rcx,%%rax\n\t"
#else
"movq %%rdi,%%rax\n\t"
#endif
STG_GLOBAL xstr(STG_RUN_JMP) "\n"
#if !defined(mingw32_HOST_OS)
STG_HIDDEN xstr(STG_RUN_JMP) "\n"
#endif
#if HAVE_SUBSECTIONS_VIA_SYMBOLS
// If we have deadstripping enabled and a label is detected as unused
// the code gets nop'd out.
".no_dead_strip " xstr(STG_RUN_JMP) "\n"
#endif
xstr(STG_RUN_JMP) ":\n\t"
"jmp *%%rax\n\t"
".globl " STG_RETURN "\n"
STG_RETURN ":\n\t"
"movq %%rbx, %%rax\n\t" /* Return value in R1 */
/*
* restore callee-saves registers. (Don't stomp on %%rax!)
*/
"addq %0, %%rsp\n\t"
"movq 0(%%rsp),%%rbx\n\t" /* restore the registers saved above */
"movq 8(%%rsp),%%rbp\n\t"
"movq 16(%%rsp),%%r12\n\t"
"movq 24(%%rsp),%%r13\n\t"
"movq 32(%%rsp),%%r14\n\t"
"movq 40(%%rsp),%%r15\n\t"
#if defined(mingw32_HOST_OS)
"movq 48(%%rsp),%%rdi\n\t"
"movq 56(%%rsp),%%rsi\n\t"
"movq 64(%%rsp),%%xmm6\n\t"
"movq 72(%%rax),%%xmm7\n\t"
"movq 80(%%rax),%%xmm8\n\t"
"movq 88(%%rax),%%xmm9\n\t"
"movq 96(%%rax),%%xmm10\n\t"
"movq 104(%%rax),%%xmm11\n\t"
"movq 112(%%rax),%%xmm12\n\t"
"movq 120(%%rax),%%xmm13\n\t"
"movq 128(%%rax),%%xmm14\n\t"
"movq 136(%%rax),%%xmm15\n\t"
#endif
"addq %1, %%rsp\n\t"
"retq"
:
: "i"(RESERVED_C_STACK_BYTES),
"i"(STG_RUN_STACK_FRAME_SIZE /* stack frame size */),
"i"(RESERVED_C_STACK_BYTES /* rbx relative to cfa (rsp) */),
"i"(RESERVED_C_STACK_BYTES + 8 /* rbp relative to cfa (rsp) */),
"i"(RESERVED_C_STACK_BYTES + 16 /* r12 relative to cfa (rsp) */),
"i"(RESERVED_C_STACK_BYTES + 24 /* r13 relative to cfa (rsp) */),
"i"(RESERVED_C_STACK_BYTES + 32 /* r14 relative to cfa (rsp) */),
"i"(RESERVED_C_STACK_BYTES + 40 /* r15 relative to cfa (rsp) */),
"i"(RESERVED_C_STACK_BYTES + STG_RUN_STACK_FRAME_SIZE
/* rip relative to cfa */)
#if !defined(darwin_HOST_OS)
, "i"((RSP_DELTA & 127) | (128 * ((RSP_DELTA >> 7) > 0)))
/* signed LEB128-encoded delta from rsp - byte 1 */
#if (RSP_DELTA >> 7) > 0
, "i"(((RSP_DELTA >> 7) & 127) | (128 * ((RSP_DELTA >> 14) > 0)))
/* signed LEB128-encoded delta from rsp - byte 2 */
#endif
#if (RSP_DELTA >> 14) > 0
, "i"(((RSP_DELTA >> 14) & 127) | (128 * ((RSP_DELTA >> 21) > 0)))
/* signed LEB128-encoded delta from rsp - byte 3 */
#endif
#if (RSP_DELTA >> 21) > 0
, "i"(((RSP_DELTA >> 21) & 127) | (128 * ((RSP_DELTA >> 28) > 0)))
/* signed LEB128-encoded delta from rsp - byte 4 */
#endif
#undef RSP_DELTA
#endif /* !defined(darwin_HOST_OS) */
);
/*
* See Note [Stack Alignment on X86]
*/
}