| Message ID | 1511780999-27757-11-git-send-email-claziss@synopsys.com |
|---|---|
| State | New |
| Headers | show |
| Series | Critical fixes | expand |
* Claudiu Zissulescu <Claudiu.Zissulescu@synopsys.com> [2017-11-27 12:09:59 +0100]: > From: Claudiu Zissulescu <claziss@gmail.com> > > The new implementation attempts to clean up the existing trampoline > implementation for ARC making it to work for linux type of systems. > > gcc/ > 2017-11-10 Claudiu Zissulescu <claziss@synopsys.com> > > * config/arc/arc.c (TARGET_TRAMPOLINE_ADJUST_ADDRESS): Delete. > (emit_store_direct): Likewise. > (arc_trampoline_adjust_address): Likewise. > (arc_asm_trampoline_template): New function. > (arc_initialize_trampoline): Use asm_trampoline_template. > (TARGET_ASM_TRAMPOLINE_TEMPLATE): Define. > * config/arc/arc.h (TRAMPOLINE_SIZE): Adjust to 16. > *config/arc/arc.md (flush_icache): Delete pattern. ^-- Missing space here. Otherwise, looks fine. Thanks, Andrew > --- > gcc/config/arc/arc.c | 89 +++++++++++++++++++++++++-------------------------- > gcc/config/arc/arc.h | 2 +- > gcc/config/arc/arc.md | 9 ------ > 3 files changed, 44 insertions(+), 56 deletions(-) > > diff --git a/gcc/config/arc/arc.c b/gcc/config/arc/arc.c > index 0eeeb42..053f3c2 100644 > --- a/gcc/config/arc/arc.c > +++ b/gcc/config/arc/arc.c > @@ -588,8 +588,6 @@ static void arc_finalize_pic (void); > > #define TARGET_TRAMPOLINE_INIT arc_initialize_trampoline > > -#define TARGET_TRAMPOLINE_ADJUST_ADDRESS arc_trampoline_adjust_address > - > #define TARGET_CAN_ELIMINATE arc_can_eliminate > > #define TARGET_FRAME_POINTER_REQUIRED arc_frame_pointer_required > @@ -3727,69 +3725,65 @@ output_shift (rtx *operands) > > /* Nested function support. */ > > -/* Directly store VALUE into memory object BLOCK at OFFSET. */ > - > -static void > -emit_store_direct (rtx block, int offset, int value) > -{ > - emit_insn (gen_store_direct (adjust_address (block, SImode, offset), > - force_reg (SImode, > - gen_int_mode (value, SImode)))); > -} > +/* Output assembler code for a block containing the constant parts of > + a trampoline, leaving space for variable parts. > > -/* Emit RTL insns to initialize the variable parts of a trampoline. > - FNADDR is an RTX for the address of the function's pure code. > - CXT is an RTX for the static chain value for the function. */ > -/* With potentially multiple shared objects loaded, and multiple stacks > - present for multiple thereds where trampolines might reside, a simple > - range check will likely not suffice for the profiler to tell if a callee > - is a trampoline. We a speedier check by making the trampoline start at > - an address that is not 4-byte aligned. > A trampoline looks like this: > > - nop_s 0x78e0 > -entry: > ld_s r12,[pcl,12] 0xd403 > ld r11,[pcl,12] 0x170c 700b > j_s [r12] 0x7c00 > - nop_s 0x78e0 > + .word function's address > + .word static chain value > + > +*/ > + > +static void > +arc_asm_trampoline_template (FILE *f) > +{ > + asm_fprintf (f, "\tld_s\t%s,[pcl,8]\n", ARC_TEMP_SCRATCH_REG); > + asm_fprintf (f, "\tld\t%s,[pcl,12]\n", reg_names[STATIC_CHAIN_REGNUM]); > + asm_fprintf (f, "\tj_s\t[%s]\n", ARC_TEMP_SCRATCH_REG); > + assemble_aligned_integer (UNITS_PER_WORD, const0_rtx); > + assemble_aligned_integer (UNITS_PER_WORD, const0_rtx); > +} > + > +/* Emit RTL insns to initialize the variable parts of a trampoline. > + FNADDR is an RTX for the address of the function's pure code. CXT > + is an RTX for the static chain value for the function. > > The fastest trampoline to execute for trampolines within +-8KB of CTX > would be: > + > add2 r11,pcl,s12 > j [limm] 0x20200f80 limm > - and that would also be faster to write to the stack by computing the offset > - from CTX to TRAMP at compile time. However, it would really be better to > - get rid of the high cost of cache invalidation when generating trampolines, > - which requires that the code part of trampolines stays constant, and > - additionally either > - - making sure that no executable code but trampolines is on the stack, > - no icache entries linger for the area of the stack from when before the > - stack was allocated, and allocating trampolines in trampoline-only > - cache lines > - or > - - allocate trampolines fram a special pool of pre-allocated trampolines. */ > + > + and that would also be faster to write to the stack by computing > + the offset from CTX to TRAMP at compile time. However, it would > + really be better to get rid of the high cost of cache invalidation > + when generating trampolines, which requires that the code part of > + trampolines stays constant, and additionally either making sure > + that no executable code but trampolines is on the stack, no icache > + entries linger for the area of the stack from when before the stack > + was allocated, and allocating trampolines in trampoline-only cache > + lines or allocate trampolines fram a special pool of pre-allocated > + trampolines. */ > > static void > arc_initialize_trampoline (rtx tramp, tree fndecl, rtx cxt) > { > rtx fnaddr = XEXP (DECL_RTL (fndecl), 0); > > - emit_store_direct (tramp, 0, TARGET_BIG_ENDIAN ? 0x78e0d403 : 0xd40378e0); > - emit_store_direct (tramp, 4, TARGET_BIG_ENDIAN ? 0x170c700b : 0x700b170c); > - emit_store_direct (tramp, 8, TARGET_BIG_ENDIAN ? 0x7c0078e0 : 0x78e07c00); > - emit_move_insn (adjust_address (tramp, SImode, 12), fnaddr); > - emit_move_insn (adjust_address (tramp, SImode, 16), cxt); > - emit_insn (gen_flush_icache (adjust_address (tramp, SImode, 0))); > -} > + emit_block_move (tramp, assemble_trampoline_template (), > + GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL); > > -/* Allow the profiler to easily distinguish trampolines from normal > - functions. */ > + emit_move_insn (adjust_address (tramp, SImode, 8), fnaddr); > + emit_move_insn (adjust_address (tramp, SImode, 12), cxt); > > -static rtx > -arc_trampoline_adjust_address (rtx addr) > -{ > - return plus_constant (Pmode, addr, 2); > + emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__clear_cache"), > + LCT_NORMAL, VOIDmode, 2, XEXP (tramp, 0), Pmode, > + plus_constant (Pmode, XEXP (tramp, 0), TRAMPOLINE_SIZE), > + Pmode); > } > > /* Add the given function declaration to emit code in JLI section. */ > @@ -11412,6 +11406,9 @@ arc_cannot_substitute_mem_equiv_p (rtx) > #undef TARGET_CANNOT_SUBSTITUTE_MEM_EQUIV_P > #define TARGET_CANNOT_SUBSTITUTE_MEM_EQUIV_P arc_cannot_substitute_mem_equiv_p > > +#undef TARGET_ASM_TRAMPOLINE_TEMPLATE > +#define TARGET_ASM_TRAMPOLINE_TEMPLATE arc_asm_trampoline_template > + > struct gcc_target targetm = TARGET_INITIALIZER; > > #include "gt-arc.h" > diff --git a/gcc/config/arc/arc.h b/gcc/config/arc/arc.h > index 8c31fb2..317a653 100644 > --- a/gcc/config/arc/arc.h > +++ b/gcc/config/arc/arc.h > @@ -829,7 +829,7 @@ extern int arc_initial_elimination_offset(int from, int to); > /* Trampolines. */ > > /* Length in units of the trampoline for entering a nested function. */ > -#define TRAMPOLINE_SIZE 20 > +#define TRAMPOLINE_SIZE 16 > > /* Alignment required for a trampoline in bits . */ > /* For actual data alignment we just need 32, no more than the stack; > diff --git a/gcc/config/arc/arc.md b/gcc/config/arc/arc.md > index 155ee6c..e1418a9 100644 > --- a/gcc/config/arc/arc.md > +++ b/gcc/config/arc/arc.md > @@ -4345,15 +4345,6 @@ archs4xd, archs4xd_slow, core_3" > (set_attr "iscompact" "true") > (set_attr "length" "2")]) > > -;; Special pattern to flush the icache. > -;; ??? Not sure what to do here. Some ARC's are known to support this. > - > -(define_insn "flush_icache" > - [(unspec_volatile [(match_operand:SI 0 "memory_operand" "m")] 0)] > - "" > - "* return \"\";" > - [(set_attr "type" "misc")]) > - > ;; Split up troublesome insns for better scheduling. > > ;; Peepholes go at the end. > -- > 1.9.1 >
diff --git a/gcc/config/arc/arc.c b/gcc/config/arc/arc.c index 0eeeb42..053f3c2 100644 --- a/gcc/config/arc/arc.c +++ b/gcc/config/arc/arc.c @@ -588,8 +588,6 @@ static void arc_finalize_pic (void); #define TARGET_TRAMPOLINE_INIT arc_initialize_trampoline -#define TARGET_TRAMPOLINE_ADJUST_ADDRESS arc_trampoline_adjust_address - #define TARGET_CAN_ELIMINATE arc_can_eliminate #define TARGET_FRAME_POINTER_REQUIRED arc_frame_pointer_required @@ -3727,69 +3725,65 @@ output_shift (rtx *operands) /* Nested function support. */ -/* Directly store VALUE into memory object BLOCK at OFFSET. */ - -static void -emit_store_direct (rtx block, int offset, int value) -{ - emit_insn (gen_store_direct (adjust_address (block, SImode, offset), - force_reg (SImode, - gen_int_mode (value, SImode)))); -} +/* Output assembler code for a block containing the constant parts of + a trampoline, leaving space for variable parts. -/* Emit RTL insns to initialize the variable parts of a trampoline. - FNADDR is an RTX for the address of the function's pure code. - CXT is an RTX for the static chain value for the function. */ -/* With potentially multiple shared objects loaded, and multiple stacks - present for multiple thereds where trampolines might reside, a simple - range check will likely not suffice for the profiler to tell if a callee - is a trampoline. We a speedier check by making the trampoline start at - an address that is not 4-byte aligned. A trampoline looks like this: - nop_s 0x78e0 -entry: ld_s r12,[pcl,12] 0xd403 ld r11,[pcl,12] 0x170c 700b j_s [r12] 0x7c00 - nop_s 0x78e0 + .word function's address + .word static chain value + +*/ + +static void +arc_asm_trampoline_template (FILE *f) +{ + asm_fprintf (f, "\tld_s\t%s,[pcl,8]\n", ARC_TEMP_SCRATCH_REG); + asm_fprintf (f, "\tld\t%s,[pcl,12]\n", reg_names[STATIC_CHAIN_REGNUM]); + asm_fprintf (f, "\tj_s\t[%s]\n", ARC_TEMP_SCRATCH_REG); + assemble_aligned_integer (UNITS_PER_WORD, const0_rtx); + assemble_aligned_integer (UNITS_PER_WORD, const0_rtx); +} + +/* Emit RTL insns to initialize the variable parts of a trampoline. + FNADDR is an RTX for the address of the function's pure code. CXT + is an RTX for the static chain value for the function. The fastest trampoline to execute for trampolines within +-8KB of CTX would be: + add2 r11,pcl,s12 j [limm] 0x20200f80 limm - and that would also be faster to write to the stack by computing the offset - from CTX to TRAMP at compile time. However, it would really be better to - get rid of the high cost of cache invalidation when generating trampolines, - which requires that the code part of trampolines stays constant, and - additionally either - - making sure that no executable code but trampolines is on the stack, - no icache entries linger for the area of the stack from when before the - stack was allocated, and allocating trampolines in trampoline-only - cache lines - or - - allocate trampolines fram a special pool of pre-allocated trampolines. */ + + and that would also be faster to write to the stack by computing + the offset from CTX to TRAMP at compile time. However, it would + really be better to get rid of the high cost of cache invalidation + when generating trampolines, which requires that the code part of + trampolines stays constant, and additionally either making sure + that no executable code but trampolines is on the stack, no icache + entries linger for the area of the stack from when before the stack + was allocated, and allocating trampolines in trampoline-only cache + lines or allocate trampolines fram a special pool of pre-allocated + trampolines. */ static void arc_initialize_trampoline (rtx tramp, tree fndecl, rtx cxt) { rtx fnaddr = XEXP (DECL_RTL (fndecl), 0); - emit_store_direct (tramp, 0, TARGET_BIG_ENDIAN ? 0x78e0d403 : 0xd40378e0); - emit_store_direct (tramp, 4, TARGET_BIG_ENDIAN ? 0x170c700b : 0x700b170c); - emit_store_direct (tramp, 8, TARGET_BIG_ENDIAN ? 0x7c0078e0 : 0x78e07c00); - emit_move_insn (adjust_address (tramp, SImode, 12), fnaddr); - emit_move_insn (adjust_address (tramp, SImode, 16), cxt); - emit_insn (gen_flush_icache (adjust_address (tramp, SImode, 0))); -} + emit_block_move (tramp, assemble_trampoline_template (), + GEN_INT (TRAMPOLINE_SIZE), BLOCK_OP_NORMAL); -/* Allow the profiler to easily distinguish trampolines from normal - functions. */ + emit_move_insn (adjust_address (tramp, SImode, 8), fnaddr); + emit_move_insn (adjust_address (tramp, SImode, 12), cxt); -static rtx -arc_trampoline_adjust_address (rtx addr) -{ - return plus_constant (Pmode, addr, 2); + emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "__clear_cache"), + LCT_NORMAL, VOIDmode, 2, XEXP (tramp, 0), Pmode, + plus_constant (Pmode, XEXP (tramp, 0), TRAMPOLINE_SIZE), + Pmode); } /* Add the given function declaration to emit code in JLI section. */ @@ -11412,6 +11406,9 @@ arc_cannot_substitute_mem_equiv_p (rtx) #undef TARGET_CANNOT_SUBSTITUTE_MEM_EQUIV_P #define TARGET_CANNOT_SUBSTITUTE_MEM_EQUIV_P arc_cannot_substitute_mem_equiv_p +#undef TARGET_ASM_TRAMPOLINE_TEMPLATE +#define TARGET_ASM_TRAMPOLINE_TEMPLATE arc_asm_trampoline_template + struct gcc_target targetm = TARGET_INITIALIZER; #include "gt-arc.h" diff --git a/gcc/config/arc/arc.h b/gcc/config/arc/arc.h index 8c31fb2..317a653 100644 --- a/gcc/config/arc/arc.h +++ b/gcc/config/arc/arc.h @@ -829,7 +829,7 @@ extern int arc_initial_elimination_offset(int from, int to); /* Trampolines. */ /* Length in units of the trampoline for entering a nested function. */ -#define TRAMPOLINE_SIZE 20 +#define TRAMPOLINE_SIZE 16 /* Alignment required for a trampoline in bits . */ /* For actual data alignment we just need 32, no more than the stack; diff --git a/gcc/config/arc/arc.md b/gcc/config/arc/arc.md index 155ee6c..e1418a9 100644 --- a/gcc/config/arc/arc.md +++ b/gcc/config/arc/arc.md @@ -4345,15 +4345,6 @@ archs4xd, archs4xd_slow, core_3" (set_attr "iscompact" "true") (set_attr "length" "2")]) -;; Special pattern to flush the icache. -;; ??? Not sure what to do here. Some ARC's are known to support this. - -(define_insn "flush_icache" - [(unspec_volatile [(match_operand:SI 0 "memory_operand" "m")] 0)] - "" - "* return \"\";" - [(set_attr "type" "misc")]) - ;; Split up troublesome insns for better scheduling. ;; Peepholes go at the end.
From: Claudiu Zissulescu <claziss@gmail.com> The new implementation attempts to clean up the existing trampoline implementation for ARC making it to work for linux type of systems. gcc/ 2017-11-10 Claudiu Zissulescu <claziss@synopsys.com> * config/arc/arc.c (TARGET_TRAMPOLINE_ADJUST_ADDRESS): Delete. (emit_store_direct): Likewise. (arc_trampoline_adjust_address): Likewise. (arc_asm_trampoline_template): New function. (arc_initialize_trampoline): Use asm_trampoline_template. (TARGET_ASM_TRAMPOLINE_TEMPLATE): Define. * config/arc/arc.h (TRAMPOLINE_SIZE): Adjust to 16. *config/arc/arc.md (flush_icache): Delete pattern. --- gcc/config/arc/arc.c | 89 +++++++++++++++++++++++++-------------------------- gcc/config/arc/arc.h | 2 +- gcc/config/arc/arc.md | 9 ------ 3 files changed, 44 insertions(+), 56 deletions(-)