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|
// Copyright 2018 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
//go:build race
#include "go_asm.h"
#include "go_tls.h"
#include "funcdata.h"
#include "textflag.h"
#include "asm_ppc64x.h"
#include "cgo/abi_ppc64x.h"
// The following functions allow calling the clang-compiled race runtime directly
// from Go code without going all the way through cgo.
// First, it's much faster (up to 50% speedup for real Go programs).
// Second, it eliminates race-related special cases from cgocall and scheduler.
// Third, in long-term it will allow to remove cyclic runtime/race dependency on cmd/go.
// A brief recap of the ppc64le calling convention.
// Arguments are passed in R3, R4, R5 ...
// SP must be 16-byte aligned.
// Note that for ppc64x, LLVM follows the standard ABI and
// expects arguments in registers, so these functions move
// the arguments from storage to the registers expected
// by the ABI.
// When calling from Go to Clang tsan code:
// R3 is the 1st argument and is usually the ThreadState*
// R4-? are the 2nd, 3rd, 4th, etc. arguments
// When calling racecalladdr:
// R8 is the call target address
// The race ctx is passed in R3 and loaded in
// racecalladdr.
//
// The sequence used to get the race ctx:
// MOVD runtime·tls_g(SB), R10 // Address of TLS variable
// MOVD 0(R10), g // g = R30
// MOVD g_racectx(g), R3 // racectx == ThreadState
// func runtime·RaceRead(addr uintptr)
// Called from instrumented Go code
TEXT runtime·raceread<ABIInternal>(SB), NOSPLIT, $0-8
MOVD R3, R4 // addr
MOVD LR, R5 // caller of this?
// void __tsan_read(ThreadState *thr, void *addr, void *pc);
MOVD $__tsan_read(SB), R8
BR racecalladdr<>(SB)
TEXT runtime·RaceRead(SB), NOSPLIT, $0-8
BR runtime·raceread(SB)
// void runtime·racereadpc(void *addr, void *callpc, void *pc)
TEXT runtime·racereadpc(SB), NOSPLIT, $0-24
MOVD addr+0(FP), R4
MOVD callpc+8(FP), R5
MOVD pc+16(FP), R6
// void __tsan_read_pc(ThreadState *thr, void *addr, void *callpc, void *pc);
MOVD $__tsan_read_pc(SB), R8
BR racecalladdr<>(SB)
// func runtime·RaceWrite(addr uintptr)
// Called from instrumented Go code
TEXT runtime·racewrite<ABIInternal>(SB), NOSPLIT, $0-8
MOVD R3, R4 // addr
MOVD LR, R5 // caller has set LR via BL inst
// void __tsan_write(ThreadState *thr, void *addr, void *pc);
MOVD $__tsan_write(SB), R8
BR racecalladdr<>(SB)
TEXT runtime·RaceWrite(SB), NOSPLIT, $0-8
JMP runtime·racewrite(SB)
// void runtime·racewritepc(void *addr, void *callpc, void *pc)
TEXT runtime·racewritepc(SB), NOSPLIT, $0-24
MOVD addr+0(FP), R4
MOVD callpc+8(FP), R5
MOVD pc+16(FP), R6
// void __tsan_write_pc(ThreadState *thr, void *addr, void *callpc, void *pc);
MOVD $__tsan_write_pc(SB), R8
BR racecalladdr<>(SB)
// func runtime·RaceReadRange(addr, size uintptr)
// Called from instrumented Go code.
TEXT runtime·racereadrange<ABIInternal>(SB), NOSPLIT, $0-16
MOVD R4, R5 // size
MOVD R3, R4 // addr
MOVD LR, R6
// void __tsan_read_range(ThreadState *thr, void *addr, uintptr size, void *pc);
MOVD $__tsan_read_range(SB), R8
BR racecalladdr<>(SB)
// void runtime·racereadrangepc1(void *addr, uintptr sz, void *pc)
TEXT runtime·racereadrangepc1(SB), NOSPLIT, $0-24
MOVD addr+0(FP), R4
MOVD size+8(FP), R5
MOVD pc+16(FP), R6
ADD $4, R6 // tsan wants return addr
// void __tsan_read_range(ThreadState *thr, void *addr, uintptr size, void *pc);
MOVD $__tsan_read_range(SB), R8
BR racecalladdr<>(SB)
TEXT runtime·RaceReadRange(SB), NOSPLIT, $0-16
BR runtime·racereadrange(SB)
// func runtime·RaceWriteRange(addr, size uintptr)
// Called from instrumented Go code.
TEXT runtime·racewriterange<ABIInternal>(SB), NOSPLIT, $0-16
MOVD R4, R5 // size
MOVD R3, R4 // addr
MOVD LR, R6
// void __tsan_write_range(ThreadState *thr, void *addr, uintptr size, void *pc);
MOVD $__tsan_write_range(SB), R8
BR racecalladdr<>(SB)
TEXT runtime·RaceWriteRange(SB), NOSPLIT, $0-16
BR runtime·racewriterange(SB)
// void runtime·racewriterangepc1(void *addr, uintptr sz, void *pc)
// Called from instrumented Go code
TEXT runtime·racewriterangepc1(SB), NOSPLIT, $0-24
MOVD addr+0(FP), R4
MOVD size+8(FP), R5
MOVD pc+16(FP), R6
ADD $4, R6 // add 4 to inst offset?
// void __tsan_write_range(ThreadState *thr, void *addr, uintptr size, void *pc);
MOVD $__tsan_write_range(SB), R8
BR racecalladdr<>(SB)
// Call a __tsan function from Go code.
// R8 = tsan function address
// R3 = *ThreadState a.k.a. g_racectx from g
// R4 = addr passed to __tsan function
//
// Otherwise, setup goroutine context and invoke racecall. Other arguments already set.
TEXT racecalladdr<>(SB), NOSPLIT, $0-0
MOVD runtime·tls_g(SB), R10
MOVD 0(R10), g
MOVD g_racectx(g), R3 // goroutine context
// Check that addr is within [arenastart, arenaend) or within [racedatastart, racedataend).
MOVD runtime·racearenastart(SB), R9
CMP R4, R9
BLT data
MOVD runtime·racearenaend(SB), R9
CMP R4, R9
BLT call
data:
MOVD runtime·racedatastart(SB), R9
CMP R4, R9
BLT ret
MOVD runtime·racedataend(SB), R9
CMP R4, R9
BGT ret
call:
// Careful!! racecall will save LR on its
// stack, which is OK as long as racecalladdr
// doesn't change in a way that generates a stack.
// racecall should return to the caller of
// recalladdr.
BR racecall<>(SB)
ret:
RET
// func runtime·racefuncenter(pc uintptr)
// Called from instrumented Go code.
TEXT runtime·racefuncenter(SB), NOSPLIT, $0-8
MOVD callpc+0(FP), R8
BR racefuncenter<>(SB)
// Common code for racefuncenter
// R11 = caller's return address
TEXT racefuncenter<>(SB), NOSPLIT, $0-0
MOVD runtime·tls_g(SB), R10
MOVD 0(R10), g
MOVD g_racectx(g), R3 // goroutine racectx aka *ThreadState
MOVD R8, R4 // caller pc set by caller in R8
// void __tsan_func_enter(ThreadState *thr, void *pc);
MOVD $__tsan_func_enter(SB), R8
BR racecall<>(SB)
RET
// func runtime·racefuncexit()
// Called from Go instrumented code.
TEXT runtime·racefuncexit(SB), NOSPLIT, $0-0
MOVD runtime·tls_g(SB), R10
MOVD 0(R10), g
MOVD g_racectx(g), R3 // goroutine racectx aka *ThreadState
// void __tsan_func_exit(ThreadState *thr);
MOVD $__tsan_func_exit(SB), R8
BR racecall<>(SB)
// Atomic operations for sync/atomic package.
// Some use the __tsan versions instead
// R6 = addr of arguments passed to this function
// R3, R4, R5 set in racecallatomic
// Load atomic in tsan
TEXT sync∕atomic·LoadInt32(SB), NOSPLIT, $0-12
GO_ARGS
// void __tsan_go_atomic32_load(ThreadState *thr, uptr cpc, uptr pc, u8 *a);
MOVD $__tsan_go_atomic32_load(SB), R8
ADD $32, R1, R6 // addr of caller's 1st arg
BR racecallatomic<>(SB)
RET
TEXT sync∕atomic·LoadInt64(SB), NOSPLIT, $0-16
GO_ARGS
// void __tsan_go_atomic64_load(ThreadState *thr, uptr cpc, uptr pc, u8 *a);
MOVD $__tsan_go_atomic64_load(SB), R8
ADD $32, R1, R6 // addr of caller's 1st arg
BR racecallatomic<>(SB)
RET
TEXT sync∕atomic·LoadUint32(SB), NOSPLIT, $0-12
GO_ARGS
BR sync∕atomic·LoadInt32(SB)
TEXT sync∕atomic·LoadUint64(SB), NOSPLIT, $0-16
GO_ARGS
BR sync∕atomic·LoadInt64(SB)
TEXT sync∕atomic·LoadUintptr(SB), NOSPLIT, $0-16
GO_ARGS
BR sync∕atomic·LoadInt64(SB)
TEXT sync∕atomic·LoadPointer(SB), NOSPLIT, $0-16
GO_ARGS
BR sync∕atomic·LoadInt64(SB)
// Store atomic in tsan
TEXT sync∕atomic·StoreInt32(SB), NOSPLIT, $0-12
GO_ARGS
// void __tsan_go_atomic32_store(ThreadState *thr, uptr cpc, uptr pc, u8 *a);
MOVD $__tsan_go_atomic32_store(SB), R8
ADD $32, R1, R6 // addr of caller's 1st arg
BR racecallatomic<>(SB)
TEXT sync∕atomic·StoreInt64(SB), NOSPLIT, $0-16
GO_ARGS
// void __tsan_go_atomic64_store(ThreadState *thr, uptr cpc, uptr pc, u8 *a);
MOVD $__tsan_go_atomic64_store(SB), R8
ADD $32, R1, R6 // addr of caller's 1st arg
BR racecallatomic<>(SB)
TEXT sync∕atomic·StoreUint32(SB), NOSPLIT, $0-12
GO_ARGS
BR sync∕atomic·StoreInt32(SB)
TEXT sync∕atomic·StoreUint64(SB), NOSPLIT, $0-16
GO_ARGS
BR sync∕atomic·StoreInt64(SB)
TEXT sync∕atomic·StoreUintptr(SB), NOSPLIT, $0-16
GO_ARGS
BR sync∕atomic·StoreInt64(SB)
// Swap in tsan
TEXT sync∕atomic·SwapInt32(SB), NOSPLIT, $0-20
GO_ARGS
// void __tsan_go_atomic32_exchange(ThreadState *thr, uptr cpc, uptr pc, u8 *a);
MOVD $__tsan_go_atomic32_exchange(SB), R8
ADD $32, R1, R6 // addr of caller's 1st arg
BR racecallatomic<>(SB)
TEXT sync∕atomic·SwapInt64(SB), NOSPLIT, $0-24
GO_ARGS
// void __tsan_go_atomic64_exchange(ThreadState *thr, uptr cpc, uptr pc, u8 *a)
MOVD $__tsan_go_atomic64_exchange(SB), R8
ADD $32, R1, R6 // addr of caller's 1st arg
BR racecallatomic<>(SB)
TEXT sync∕atomic·SwapUint32(SB), NOSPLIT, $0-20
GO_ARGS
BR sync∕atomic·SwapInt32(SB)
TEXT sync∕atomic·SwapUint64(SB), NOSPLIT, $0-24
GO_ARGS
BR sync∕atomic·SwapInt64(SB)
TEXT sync∕atomic·SwapUintptr(SB), NOSPLIT, $0-24
GO_ARGS
BR sync∕atomic·SwapInt64(SB)
// Add atomic in tsan
TEXT sync∕atomic·AddInt32(SB), NOSPLIT, $0-20
GO_ARGS
// void __tsan_go_atomic32_fetch_add(ThreadState *thr, uptr cpc, uptr pc, u8 *a);
MOVD $__tsan_go_atomic32_fetch_add(SB), R8
ADD $64, R1, R6 // addr of caller's 1st arg
BL racecallatomic<>(SB)
// The tsan fetch_add result is not as expected by Go,
// so the 'add' must be added to the result.
MOVW add+8(FP), R3 // The tsa fetch_add does not return the
MOVW ret+16(FP), R4 // result as expected by go, so fix it.
ADD R3, R4, R3
MOVW R3, ret+16(FP)
RET
TEXT sync∕atomic·AddInt64(SB), NOSPLIT, $0-24
GO_ARGS
// void __tsan_go_atomic64_fetch_add(ThreadState *thr, uptr cpc, uptr pc, u8 *a);
MOVD $__tsan_go_atomic64_fetch_add(SB), R8
ADD $64, R1, R6 // addr of caller's 1st arg
BL racecallatomic<>(SB)
// The tsan fetch_add result is not as expected by Go,
// so the 'add' must be added to the result.
MOVD add+8(FP), R3
MOVD ret+16(FP), R4
ADD R3, R4, R3
MOVD R3, ret+16(FP)
RET
TEXT sync∕atomic·AddUint32(SB), NOSPLIT, $0-20
GO_ARGS
BR sync∕atomic·AddInt32(SB)
TEXT sync∕atomic·AddUint64(SB), NOSPLIT, $0-24
GO_ARGS
BR sync∕atomic·AddInt64(SB)
TEXT sync∕atomic·AddUintptr(SB), NOSPLIT, $0-24
GO_ARGS
BR sync∕atomic·AddInt64(SB)
// CompareAndSwap in tsan
TEXT sync∕atomic·CompareAndSwapInt32(SB), NOSPLIT, $0-17
GO_ARGS
// void __tsan_go_atomic32_compare_exchange(
// ThreadState *thr, uptr cpc, uptr pc, u8 *a)
MOVD $__tsan_go_atomic32_compare_exchange(SB), R8
ADD $32, R1, R6 // addr of caller's 1st arg
BR racecallatomic<>(SB)
TEXT sync∕atomic·CompareAndSwapInt64(SB), NOSPLIT, $0-25
GO_ARGS
// void __tsan_go_atomic32_compare_exchange(
// ThreadState *thr, uptr cpc, uptr pc, u8 *a)
MOVD $__tsan_go_atomic64_compare_exchange(SB), R8
ADD $32, R1, R6 // addr of caller's 1st arg
BR racecallatomic<>(SB)
TEXT sync∕atomic·CompareAndSwapUint32(SB), NOSPLIT, $0-17
GO_ARGS
BR sync∕atomic·CompareAndSwapInt32(SB)
TEXT sync∕atomic·CompareAndSwapUint64(SB), NOSPLIT, $0-25
GO_ARGS
BR sync∕atomic·CompareAndSwapInt64(SB)
TEXT sync∕atomic·CompareAndSwapUintptr(SB), NOSPLIT, $0-25
GO_ARGS
BR sync∕atomic·CompareAndSwapInt64(SB)
// Common function used to call tsan's atomic functions
// R3 = *ThreadState
// R4 = TODO: What's this supposed to be?
// R5 = caller pc
// R6 = addr of incoming arg list
// R8 contains addr of target function.
TEXT racecallatomic<>(SB), NOSPLIT, $0-0
// Trigger SIGSEGV early if address passed to atomic function is bad.
MOVD (R6), R7 // 1st arg is addr
MOVB (R7), R9 // segv here if addr is bad
// Check that addr is within [arenastart, arenaend) or within [racedatastart, racedataend).
MOVD runtime·racearenastart(SB), R9
CMP R7, R9
BLT racecallatomic_data
MOVD runtime·racearenaend(SB), R9
CMP R7, R9
BLT racecallatomic_ok
racecallatomic_data:
MOVD runtime·racedatastart(SB), R9
CMP R7, R9
BLT racecallatomic_ignore
MOVD runtime·racedataend(SB), R9
CMP R7, R9
BGE racecallatomic_ignore
racecallatomic_ok:
// Addr is within the good range, call the atomic function.
MOVD runtime·tls_g(SB), R10
MOVD 0(R10), g
MOVD g_racectx(g), R3 // goroutine racectx aka *ThreadState
MOVD R8, R5 // pc is the function called
MOVD (R1), R4 // caller pc from stack
BL racecall<>(SB) // BL needed to maintain stack consistency
RET //
racecallatomic_ignore:
// Addr is outside the good range.
// Call __tsan_go_ignore_sync_begin to ignore synchronization during the atomic op.
// An attempt to synchronize on the address would cause crash.
MOVD R8, R15 // save the original function
MOVD R6, R17 // save the original arg list addr
MOVD $__tsan_go_ignore_sync_begin(SB), R8 // func addr to call
MOVD runtime·tls_g(SB), R10
MOVD 0(R10), g
MOVD g_racectx(g), R3 // goroutine context
BL racecall<>(SB)
MOVD R15, R8 // restore the original function
MOVD R17, R6 // restore arg list addr
// Call the atomic function.
// racecall will call LLVM race code which might clobber r30 (g)
MOVD runtime·tls_g(SB), R10
MOVD 0(R10), g
MOVD g_racectx(g), R3
MOVD R8, R4 // pc being called same TODO as above
MOVD (R1), R5 // caller pc from latest LR
BL racecall<>(SB)
// Call __tsan_go_ignore_sync_end.
MOVD $__tsan_go_ignore_sync_end(SB), R8
MOVD g_racectx(g), R3 // goroutine context g should still be good?
BL racecall<>(SB)
RET
// void runtime·racecall(void(*f)(...), ...)
// Calls C function f from race runtime and passes up to 4 arguments to it.
// The arguments are never heap-object-preserving pointers, so we pretend there are no arguments.
TEXT runtime·racecall(SB), NOSPLIT, $0-0
MOVD fn+0(FP), R8
MOVD arg0+8(FP), R3
MOVD arg1+16(FP), R4
MOVD arg2+24(FP), R5
MOVD arg3+32(FP), R6
JMP racecall<>(SB)
// Finds g0 and sets its stack
// Arguments were loaded for call from Go to C
TEXT racecall<>(SB), NOSPLIT, $0-0
// Set the LR slot for the ppc64 ABI
MOVD LR, R10
MOVD R10, 0(R1) // Go expectation
MOVD R10, 16(R1) // C ABI
// Get info from the current goroutine
MOVD runtime·tls_g(SB), R10 // g offset in TLS
MOVD 0(R10), g
MOVD g_m(g), R7 // m for g
MOVD R1, R16 // callee-saved, preserved across C call
MOVD m_g0(R7), R10 // g0 for m
CMP R10, g // same g0?
BEQ call // already on g0
MOVD (g_sched+gobuf_sp)(R10), R1 // switch R1
call:
// prepare frame for C ABI
SUB $32, R1 // create frame for callee saving LR, CR, R2 etc.
RLDCR $0, R1, $~15, R1 // align SP to 16 bytes
MOVD R8, CTR // R8 = caller addr
MOVD R8, R12 // expected by PPC64 ABI
BL (CTR)
XOR R0, R0 // clear R0 on return from Clang
MOVD R16, R1 // restore R1; R16 nonvol in Clang
MOVD runtime·tls_g(SB), R10 // find correct g
MOVD 0(R10), g
MOVD 16(R1), R10 // LR was saved away, restore for return
MOVD R10, LR
RET
// C->Go callback thunk that allows to call runtime·racesymbolize from C code.
// Direct Go->C race call has only switched SP, finish g->g0 switch by setting correct g.
// The overall effect of Go->C->Go call chain is similar to that of mcall.
// RARG0 contains command code. RARG1 contains command-specific context.
// See racecallback for command codes.
TEXT runtime·racecallbackthunk(SB), NOSPLIT|NOFRAME, $0
// Handle command raceGetProcCmd (0) here.
// First, code below assumes that we are on curg, while raceGetProcCmd
// can be executed on g0. Second, it is called frequently, so will
// benefit from this fast path.
MOVD $0, R0 // clear R0 since we came from C code
CMP R3, $0
BNE rest
// Inline raceGetProdCmd without clobbering callee-save registers.
MOVD runtime·tls_g(SB), R10
MOVD 0(R10), R11
MOVD g_m(R11), R3
MOVD m_p(R3), R3
MOVD p_raceprocctx(R3), R3
MOVD R3, (R4)
RET
rest:
// Save registers according to the host PPC64 ABI
// and reserve 16B for argument storage.
STACK_AND_SAVE_HOST_TO_GO_ABI(16)
// Load g, and switch to g0 if not already on it.
MOVD runtime·tls_g(SB), R10
MOVD 0(R10), g
MOVD g_m(g), R7
MOVD m_g0(R7), R8
CMP g, R8
BEQ noswitch
MOVD R8, g // set g = m->g0
noswitch:
BL runtime·racecallback<ABIInternal>(SB)
UNSTACK_AND_RESTORE_GO_TO_HOST_ABI(16)
RET
// tls_g, g value for each thread in TLS
GLOBL runtime·tls_g+0(SB), TLSBSS+DUPOK, $8
|
