diff options
| -rw-r--r-- | compiler/nativeGen/X86/Instr.hs | 5 | ||||
| -rw-r--r-- | rts/RtsSymbols.c | 2 | ||||
| -rw-r--r-- | rts/Schedule.c | 17 | ||||
| -rw-r--r-- | rts/StgCRun.c | 49 | ||||
| -rw-r--r-- | rts/StgRun.h | 4 |
5 files changed, 33 insertions, 44 deletions
diff --git a/compiler/nativeGen/X86/Instr.hs b/compiler/nativeGen/X86/Instr.hs index 7e47860143..d4efd83be7 100644 --- a/compiler/nativeGen/X86/Instr.hs +++ b/compiler/nativeGen/X86/Instr.hs @@ -819,13 +819,14 @@ x86_mkJumpInstr id -- In essense each allocation larger than a page size needs to be chunked and -- a probe emitted after each page allocation. You have to hit the guard -- page so the kernel can map in the next page, otherwise you'll segfault. +-- See Note [Windows stack allocations]. -- needs_probe_call :: Platform -> Int -> Bool needs_probe_call platform amount = case platformOS platform of OSMinGW32 -> case platformArch platform of ArchX86 -> amount > (4 * 1024) - ArchX86_64 -> amount > (8 * 1024) + ArchX86_64 -> amount > (4 * 1024) _ -> False _ -> False @@ -849,7 +850,7 @@ x86_mkStackAllocInstr platform amount -- -- We emit a call because the stack probes are quite involved and -- would bloat code size a lot. GHC doesn't really have an -Os. - -- __chkstk is guaranteed to leave all nonvolatile registers and AX + -- ___chkstk is guaranteed to leave all nonvolatile registers and AX -- untouched. It's part of the standard prologue code for any Windows -- function dropping the stack more than a page. -- See Note [Windows stack layout] diff --git a/rts/RtsSymbols.c b/rts/RtsSymbols.c index 442b92a31a..d1d041c0f1 100644 --- a/rts/RtsSymbols.c +++ b/rts/RtsSymbols.c @@ -134,7 +134,7 @@ SymI_HasProto(rts_InstallConsoleEvent) \ SymI_HasProto(rts_ConsoleHandlerDone) \ SymI_HasProto(atexit) \ - RTS_WIN32_ONLY(SymI_NeedsProto(__chkstk_ms)) \ + RTS_WIN32_ONLY(SymI_NeedsProto(___chkstk_ms)) \ RTS_WIN64_ONLY(SymI_NeedsProto(___chkstk_ms)) \ RTS_WIN32_ONLY(SymI_HasProto(_imp___environ)) \ RTS_WIN64_ONLY(SymI_HasProto(__imp__environ)) \ diff --git a/rts/Schedule.c b/rts/Schedule.c index 9323915dfe..22787c4cfb 100644 --- a/rts/Schedule.c +++ b/rts/Schedule.c @@ -136,7 +136,6 @@ static Capability *schedule (Capability *initialCapability, Task *task); // abstracted only to make the structure and control flow of the // scheduler clearer. // -static void schedulePreLoop (void); static void scheduleFindWork (Capability **pcap); #if defined(THREADED_RTS) static void scheduleYield (Capability **pcap, Task *task); @@ -205,8 +204,6 @@ schedule (Capability *initialCapability, Task *task) debugTrace (DEBUG_sched, "cap %d: schedule()", initialCapability->no); - schedulePreLoop(); - // ----------------------------------------------------------- // Scheduler loop starts here: @@ -599,20 +596,6 @@ promoteInRunQueue (Capability *cap, StgTSO *tso) pushOnRunQueue(cap, tso); } -/* ---------------------------------------------------------------------------- - * Setting up the scheduler loop - * ------------------------------------------------------------------------- */ - -static void -schedulePreLoop(void) -{ - // initialisation for scheduler - what cannot go into initScheduler() - -#if defined(mingw32_HOST_OS) && !defined(USE_MINIINTERPRETER) - win32AllocStack(); -#endif -} - /* ----------------------------------------------------------------------------- * scheduleFindWork() * diff --git a/rts/StgCRun.c b/rts/StgCRun.c index 934926e0f3..ddb19b468b 100644 --- a/rts/StgCRun.c +++ b/rts/StgCRun.c @@ -89,25 +89,6 @@ StgFunPtr StgReturn(void) } #else /* !USE_MINIINTERPRETER */ - -#if defined(mingw32_HOST_OS) -/* - * Note [Windows Stack allocations] - * - * On windows the stack has to be allocated 4k at a time, otherwise - * we get a segfault. The C compiler knows how to do this (it calls - * _alloca()), so we make sure that we can allocate as much stack as - * we need. However since we are doing a local stack allocation and the value - * isn't valid outside the frame, compilers are free to optimize this allocation - * and the corresponding stack check away. So to prevent that we request that - * this function never be optimized (See #14669). */ -STG_NO_OPTIMIZE StgWord8 *win32AllocStack(void) -{ - StgWord8 stack[RESERVED_C_STACK_BYTES + 16 + 12]; - return stack; -} -#endif - /* ----------------------------------------------------------------------------- x86 architecture -------------------------------------------------------------------------- */ @@ -159,7 +140,21 @@ STG_NO_OPTIMIZE StgWord8 *win32AllocStack(void) * * If you edit the sequence below be sure to update the unwinding information * for stg_stop_thread in StgStartup.cmm. - */ + * + * Note [Windows Stack allocations] + * + * On windows the stack has to be allocated 4k at a time, otherwise + * we get a segfault. This is done by using a helper ___chkstk_ms that is + * provided by libgcc. The Haskell side already knows how to handle this +(see GHC.CmmToAsm.X86.Instr.needs_probe_call) + * but we need to do the same from STG. Previously we would drop the stack + * in StgRun but would only make it valid whenever the scheduler loop ran. + * + * This approach was fundamentally broken in that it falls apart when you + * take a signal from the OS (See #14669, #18601, #18548 and #18496). + * Concretely this means we must always keep the stack valid. + * */ + static void GNUC3_ATTRIBUTE(used) StgRunIsImplementedInAssembler(void) @@ -179,7 +174,13 @@ StgRunIsImplementedInAssembler(void) * bytes from here - this is a requirement of the C ABI, so * that C code can assign SSE2 registers directly to/from * stack locations. + * + * See Note [Windows Stack allocations] */ +#if defined(mingw32_HOST_OS) + "movl %0, %%eax\n\t" + "call ___chkstk_ms\n\t" +#endif "subl %0, %%esp\n\t" /* @@ -376,6 +377,14 @@ StgRunIsImplementedInAssembler(void) STG_HIDDEN STG_RUN "\n" #endif STG_RUN ":\n\t" + /* + * See Note [Windows Stack allocations] + */ +#if defined(mingw32_HOST_OS) + "movq %1, %%rax\n\t" + "addq %0, %%rax\n\t" + "callq ___chkstk_ms\n\t" +#endif "subq %1, %%rsp\n\t" "movq %%rsp, %%rax\n\t" "subq %0, %%rsp\n\t" diff --git a/rts/StgRun.h b/rts/StgRun.h index 356c40dba2..f7c042c853 100644 --- a/rts/StgRun.h +++ b/rts/StgRun.h @@ -9,7 +9,3 @@ #pragma once RTS_PRIVATE StgRegTable * StgRun (StgFunPtr f, StgRegTable *basereg); - -#if defined(mingw32_HOST_OS) -StgWord8 *win32AllocStack(void); -#endif |