From b55c288db921212cc0eb821cf2233250c025beb8 Mon Sep 17 00:00:00 2001 From: Max Filippov Date: Tue, 22 Nov 2016 14:17:27 -0800 Subject: gcc: backport fix for xtensa PR target/78118 This fixes ICE when building libgcc for xtensa with call0 ABI. Signed-off-by: Max Filippov diff --git a/patches/gcc/6.2.0/871-xtensa-Fix-PR-target-78118.patch b/patches/gcc/6.2.0/871-xtensa-Fix-PR-target-78118.patch new file mode 100644 index 0000000..c6ae103 --- /dev/null +++ b/patches/gcc/6.2.0/871-xtensa-Fix-PR-target-78118.patch @@ -0,0 +1,318 @@ +From bdda1689faf608ad7c83b5bd2e21a236b0047579 Mon Sep 17 00:00:00 2001 +From: Max Filippov +Date: Wed, 26 Oct 2016 08:02:51 +0000 +Subject: [PATCH] xtensa: Fix PR target/78118 + +It started failing after the following commit: 32e90dc6a0cda45 ("PR +rtl-optimization/61047"). + +The change that made xtensa backend go ICE looks completely unrelated, +and indeed, the issue is caused by the side effect of +compute_frame_size() function call hidden in the +INITIAL_ELIMINATION_OFFSET macro. This call updates the value of the +xtensa_current_frame_size static variable, used in "return" instruction +predicate. Prior to the change the value of xtensa_current_frame_size was +set to 0 after the end of epilogue generation, which enabled the "return" +instruction for the CALL0 ABI, but after the change the additional +INITIAL_ELIMINATION_OFFSET calls make xtensa_current_frame_size non-zero +and "return" pattern unavailable. + +Get rid of the global xtensa_current_frame_size and +xtensa_callee_save_size variables by moving them into the +machine_function structure. Implement predicate for the "return" pattern +as a function. Don't communicate completion of epilogue generation +through zeroing of xtensa_current_frame_size, add explicit epilogue_done +variable to the machine_function structure. Don't update stack frame +layout after the completion of reload. + +2016-10-26 Max Filippov +gcc/ + * config/xtensa/xtensa-protos.h + (xtensa_use_return_instruction_p): New prototype. + * config/xtensa/xtensa.c (xtensa_current_frame_size, + xtensa_callee_save_size): Remove. + (struct machine_function): Add new fields: current_frame_size, + callee_save_size, frame_laid_out and epilogue_done. + (compute_frame_size, xtensa_expand_prologue, + xtensa_expand_epilogue): Replace xtensa_callee_save_size with + cfun->machine->callee_save_size and xtensa_current_frame_size + with cfun->machine->current_frame_size. + (compute_frame_size): Update cfun->machine->frame_laid_out and + don't update frame layout after reload completion. + (xtensa_expand_epilogue): Set cfun->machine->epilogue_done + instead of zeroing xtensa_current_frame_size. + (xtensa_use_return_instruction_p): New function. + * config/xtensa/xtensa.h (xtensa_current_frame_size): Remove + declaration. + (INITIAL_ELIMINATION_OFFSET): Use return value of + compute_frame_size instead of xtensa_current_frame_size value. + * config/xtensa/xtensa.md ("return" pattern): Use new predicate + function xtensa_use_return_instruction_p instead of inline code. + +Signed-off-by: Max Filippov +--- + gcc/config/xtensa/xtensa-protos.h | 1 + + gcc/config/xtensa/xtensa.c | 82 ++++++++++++++++++++++++--------------- + gcc/config/xtensa/xtensa.h | 6 +-- + gcc/config/xtensa/xtensa.md | 2 +- + 4 files changed, 55 insertions(+), 36 deletions(-) + +diff --git a/gcc/config/xtensa/xtensa-protos.h b/gcc/config/xtensa/xtensa-protos.h +index f2ca526..873557f 100644 +--- a/gcc/config/xtensa/xtensa-protos.h ++++ b/gcc/config/xtensa/xtensa-protos.h +@@ -68,6 +68,7 @@ extern rtx xtensa_return_addr (int, rtx); + extern void xtensa_setup_frame_addresses (void); + extern int xtensa_dbx_register_number (int); + extern long compute_frame_size (int); ++extern bool xtensa_use_return_instruction_p (void); + extern void xtensa_expand_prologue (void); + extern void xtensa_expand_epilogue (void); + extern void order_regs_for_local_alloc (void); +diff --git a/gcc/config/xtensa/xtensa.c b/gcc/config/xtensa/xtensa.c +index 64d089b..e49f784 100644 +--- a/gcc/config/xtensa/xtensa.c ++++ b/gcc/config/xtensa/xtensa.c +@@ -78,11 +78,6 @@ enum internal_test + can support a given mode. */ + char xtensa_hard_regno_mode_ok[(int) MAX_MACHINE_MODE][FIRST_PSEUDO_REGISTER]; + +-/* Current frame size calculated by compute_frame_size. */ +-unsigned xtensa_current_frame_size; +-/* Callee-save area size in the current frame calculated by compute_frame_size. */ +-int xtensa_callee_save_size; +- + /* Largest block move to handle in-line. */ + #define LARGEST_MOVE_RATIO 15 + +@@ -94,6 +89,13 @@ struct GTY(()) machine_function + bool vararg_a7; + rtx vararg_a7_copy; + rtx_insn *set_frame_ptr_insn; ++ /* Current frame size calculated by compute_frame_size. */ ++ unsigned current_frame_size; ++ /* Callee-save area size in the current frame calculated by ++ compute_frame_size. */ ++ int callee_save_size; ++ bool frame_laid_out; ++ bool epilogue_done; + }; + + /* Vector, indexed by hard register number, which contains 1 for a +@@ -2628,24 +2630,29 @@ compute_frame_size (int size) + { + int regno; + ++ if (reload_completed && cfun->machine->frame_laid_out) ++ return cfun->machine->current_frame_size; ++ + /* Add space for the incoming static chain value. */ + if (cfun->static_chain_decl != NULL) + size += (1 * UNITS_PER_WORD); + +- xtensa_callee_save_size = 0; ++ cfun->machine->callee_save_size = 0; + for (regno = 0; regno < FIRST_PSEUDO_REGISTER; ++regno) + { + if (xtensa_call_save_reg(regno)) +- xtensa_callee_save_size += UNITS_PER_WORD; ++ cfun->machine->callee_save_size += UNITS_PER_WORD; + } + +- xtensa_current_frame_size = ++ cfun->machine->current_frame_size = + XTENSA_STACK_ALIGN (size +- + xtensa_callee_save_size ++ + cfun->machine->callee_save_size + + crtl->outgoing_args_size + + (WINDOW_SIZE * UNITS_PER_WORD)); +- xtensa_callee_save_size = XTENSA_STACK_ALIGN (xtensa_callee_save_size); +- return xtensa_current_frame_size; ++ cfun->machine->callee_save_size = ++ XTENSA_STACK_ALIGN (cfun->machine->callee_save_size); ++ cfun->machine->frame_laid_out = true; ++ return cfun->machine->current_frame_size; + } + + +@@ -2696,6 +2703,7 @@ xtensa_expand_prologue (void) + { + int regno; + HOST_WIDE_INT offset = 0; ++ int callee_save_size = cfun->machine->callee_save_size; + + /* -128 is a limit of single addi instruction. */ + if (total_size > 0 && total_size <= 128) +@@ -2709,7 +2717,7 @@ xtensa_expand_prologue (void) + add_reg_note (insn, REG_FRAME_RELATED_EXPR, note_rtx); + offset = total_size - UNITS_PER_WORD; + } +- else if (xtensa_callee_save_size) ++ else if (callee_save_size) + { + /* 1020 is maximal s32i offset, if the frame is bigger than that + * we move sp to the end of callee-saved save area, save and then +@@ -2717,13 +2725,13 @@ xtensa_expand_prologue (void) + if (total_size > 1024) + { + insn = emit_insn (gen_addsi3 (stack_pointer_rtx, stack_pointer_rtx, +- GEN_INT (-xtensa_callee_save_size))); ++ GEN_INT (-callee_save_size))); + RTX_FRAME_RELATED_P (insn) = 1; + note_rtx = gen_rtx_SET (stack_pointer_rtx, + plus_constant (Pmode, stack_pointer_rtx, +- -xtensa_callee_save_size)); ++ -callee_save_size)); + add_reg_note (insn, REG_FRAME_RELATED_EXPR, note_rtx); +- offset = xtensa_callee_save_size - UNITS_PER_WORD; ++ offset = callee_save_size - UNITS_PER_WORD; + } + else + { +@@ -2759,13 +2767,13 @@ xtensa_expand_prologue (void) + { + rtx tmp_reg = gen_rtx_REG (Pmode, A9_REG); + emit_move_insn (tmp_reg, GEN_INT (total_size - +- xtensa_callee_save_size)); ++ callee_save_size)); + insn = emit_insn (gen_subsi3 (stack_pointer_rtx, + stack_pointer_rtx, tmp_reg)); + RTX_FRAME_RELATED_P (insn) = 1; + note_rtx = gen_rtx_SET (stack_pointer_rtx, + plus_constant (Pmode, stack_pointer_rtx, +- xtensa_callee_save_size - ++ callee_save_size - + total_size)); + add_reg_note (insn, REG_FRAME_RELATED_EXPR, note_rtx); + } +@@ -2833,21 +2841,21 @@ xtensa_expand_epilogue (void) + int regno; + HOST_WIDE_INT offset; + +- if (xtensa_current_frame_size > (frame_pointer_needed ? 127 : 1024)) ++ if (cfun->machine->current_frame_size > (frame_pointer_needed ? 127 : 1024)) + { + rtx tmp_reg = gen_rtx_REG (Pmode, A9_REG); +- emit_move_insn (tmp_reg, GEN_INT (xtensa_current_frame_size - +- xtensa_callee_save_size)); ++ emit_move_insn (tmp_reg, GEN_INT (cfun->machine->current_frame_size - ++ cfun->machine->callee_save_size)); + emit_insn (gen_addsi3 (stack_pointer_rtx, frame_pointer_needed ? + hard_frame_pointer_rtx : stack_pointer_rtx, + tmp_reg)); +- offset = xtensa_callee_save_size - UNITS_PER_WORD; ++ offset = cfun->machine->callee_save_size - UNITS_PER_WORD; + } + else + { + if (frame_pointer_needed) + emit_move_insn (stack_pointer_rtx, hard_frame_pointer_rtx); +- offset = xtensa_current_frame_size - UNITS_PER_WORD; ++ offset = cfun->machine->current_frame_size - UNITS_PER_WORD; + } + + /* Prevent reordering of saved a0 update and loading it back from +@@ -2867,16 +2875,16 @@ xtensa_expand_epilogue (void) + } + } + +- if (xtensa_current_frame_size > 0) ++ if (cfun->machine->current_frame_size > 0) + { + if (frame_pointer_needed || /* always reachable with addi */ +- xtensa_current_frame_size > 1024 || +- xtensa_current_frame_size <= 127) ++ cfun->machine->current_frame_size > 1024 || ++ cfun->machine->current_frame_size <= 127) + { +- if (xtensa_current_frame_size <= 127) +- offset = xtensa_current_frame_size; ++ if (cfun->machine->current_frame_size <= 127) ++ offset = cfun->machine->current_frame_size; + else +- offset = xtensa_callee_save_size; ++ offset = cfun->machine->callee_save_size; + + emit_insn (gen_addsi3 (stack_pointer_rtx, + stack_pointer_rtx, +@@ -2885,7 +2893,8 @@ xtensa_expand_epilogue (void) + else + { + rtx tmp_reg = gen_rtx_REG (Pmode, A9_REG); +- emit_move_insn (tmp_reg, GEN_INT (xtensa_current_frame_size)); ++ emit_move_insn (tmp_reg, ++ GEN_INT (cfun->machine->current_frame_size)); + emit_insn (gen_addsi3 (stack_pointer_rtx, stack_pointer_rtx, + tmp_reg)); + } +@@ -2896,11 +2905,22 @@ xtensa_expand_epilogue (void) + stack_pointer_rtx, + EH_RETURN_STACKADJ_RTX)); + } +- xtensa_current_frame_size = 0; +- xtensa_callee_save_size = 0; ++ cfun->machine->epilogue_done = true; + emit_jump_insn (gen_return ()); + } + ++bool ++xtensa_use_return_instruction_p (void) ++{ ++ if (!reload_completed) ++ return false; ++ if (TARGET_WINDOWED_ABI) ++ return true; ++ if (compute_frame_size (get_frame_size ()) == 0) ++ return true; ++ return cfun->machine->epilogue_done; ++} ++ + void + xtensa_set_return_address (rtx address, rtx scratch) + { +diff --git a/gcc/config/xtensa/xtensa.h b/gcc/config/xtensa/xtensa.h +index 82e9900..58eb1b2 100644 +--- a/gcc/config/xtensa/xtensa.h ++++ b/gcc/config/xtensa/xtensa.h +@@ -23,8 +23,6 @@ along with GCC; see the file COPYING3. If not see + + /* External variables defined in xtensa.c. */ + +-extern unsigned xtensa_current_frame_size; +- + /* Macros used in the machine description to select various Xtensa + configuration options. */ + #ifndef XCHAL_HAVE_MUL32_HIGH +@@ -477,14 +475,14 @@ enum reg_class + /* Specify the initial difference between the specified pair of registers. */ + #define INITIAL_ELIMINATION_OFFSET(FROM, TO, OFFSET) \ + do { \ +- compute_frame_size (get_frame_size ()); \ ++ long frame_size = compute_frame_size (get_frame_size ()); \ + switch (FROM) \ + { \ + case FRAME_POINTER_REGNUM: \ + (OFFSET) = 0; \ + break; \ + case ARG_POINTER_REGNUM: \ +- (OFFSET) = xtensa_current_frame_size; \ ++ (OFFSET) = frame_size; \ + break; \ + default: \ + gcc_unreachable (); \ +diff --git a/gcc/config/xtensa/xtensa.md b/gcc/config/xtensa/xtensa.md +index db54a12..fcdb6c8 100644 +--- a/gcc/config/xtensa/xtensa.md ++++ b/gcc/config/xtensa/xtensa.md +@@ -1663,7 +1663,7 @@ + (define_insn "return" + [(return) + (use (reg:SI A0_REG))] +- "(TARGET_WINDOWED_ABI || !xtensa_current_frame_size) && reload_completed" ++ "xtensa_use_return_instruction_p ()" + { + return TARGET_WINDOWED_ABI ? + (TARGET_DENSITY ? "retw.n" : "retw") : +-- +2.1.4 + -- cgit v0.10.2-6-g49f6