From 2cf63121e9640348fa3d917dfb247da545255c61 Mon Sep 17 00:00:00 2001 From: "Maciej W. Rozycki" Date: Tue, 15 Nov 2016 15:04:10 +0000 Subject: [PATCH] MIPS/GCC: Mark trailing labels with `.insn' gcc/ * config/mips/mips.c (mips16_emit_constants): Emit `consttable' insn at the beginning of the constant pool. (mips_insert_insn_pseudos): New function. (mips_machine_reorg2): Call it. * config/mips/mips.md (unspec): Add UNSPEC_CONSTTABLE and UNSPEC_INSN_PSEUDO enum values. (insn_pseudo, consttable): New insns. gcc/testsuite/ * gcc.target/mips/insn-casesi.c: New test case. * gcc.target/mips/insn-pseudo-1.c: New test case. * gcc.target/mips/insn-pseudo-2.c: New test case. * gcc.target/mips/insn-pseudo-3.c: New test case. * gcc.target/mips/insn-pseudo-4.c: New test case. * gcc.target/mips/insn-tablejump.c: New test case. From-SVN: r242424 --- gcc/ChangeLog | 10 ++ gcc/config/mips/mips.c | 43 +++++++ gcc/config/mips/mips.md | 19 +++ gcc/testsuite/ChangeLog | 9 ++ gcc/testsuite/gcc.target/mips/insn-casesi.c | 112 ++++++++++++++++++ gcc/testsuite/gcc.target/mips/insn-pseudo-1.c | 23 ++++ gcc/testsuite/gcc.target/mips/insn-pseudo-2.c | 23 ++++ gcc/testsuite/gcc.target/mips/insn-pseudo-3.c | 23 ++++ gcc/testsuite/gcc.target/mips/insn-pseudo-4.c | 27 +++++ .../gcc.target/mips/insn-tablejump.c | 98 +++++++++++++++ 10 files changed, 387 insertions(+) create mode 100644 gcc/testsuite/gcc.target/mips/insn-casesi.c create mode 100644 gcc/testsuite/gcc.target/mips/insn-pseudo-1.c create mode 100644 gcc/testsuite/gcc.target/mips/insn-pseudo-2.c create mode 100644 gcc/testsuite/gcc.target/mips/insn-pseudo-3.c create mode 100644 gcc/testsuite/gcc.target/mips/insn-pseudo-4.c create mode 100644 gcc/testsuite/gcc.target/mips/insn-tablejump.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index c4a660f0cff..b91bf89652c 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,13 @@ +2016-11-15 Maciej W. Rozycki + + * config/mips/mips.c (mips16_emit_constants): Emit `consttable' + insn at the beginning of the constant pool. + (mips_insert_insn_pseudos): New function. + (mips_machine_reorg2): Call it. + * config/mips/mips.md (unspec): Add UNSPEC_CONSTTABLE and + UNSPEC_INSN_PSEUDO enum values. + (insn_pseudo, consttable): New insns. + 2016-11-15 Michael Matz PR missed-optimization/77881 diff --git a/gcc/config/mips/mips.c b/gcc/config/mips/mips.c index 552b73adaf7..44cdeb72c1d 100644 --- a/gcc/config/mips/mips.c +++ b/gcc/config/mips/mips.c @@ -17140,6 +17140,8 @@ mips16_emit_constants (struct mips16_constant *constants, rtx_insn *insn) int align; align = 0; + if (constants) + insn = emit_insn_after (gen_consttable (), insn); for (c = constants; c != NULL; c = next) { /* If necessary, increase the alignment of PC. */ @@ -19015,6 +19017,46 @@ mips16_split_long_branches (void) while (something_changed); } +/* Insert a `.insn' assembly pseudo-op after any labels followed by + a MIPS16 constant pool or no insn at all. This is needed so that + targets that have been optimized away are still marked as code + and therefore branches that remained and point to them are known + to retain the ISA mode and as such can be successfully assembled. */ + +static void +mips_insert_insn_pseudos (void) +{ + bool insn_pseudo_needed = TRUE; + rtx_insn *insn; + + for (insn = get_last_insn (); insn != NULL_RTX; insn = PREV_INSN (insn)) + switch (GET_CODE (insn)) + { + case INSN: + if (GET_CODE (PATTERN (insn)) == UNSPEC_VOLATILE + && XINT (PATTERN (insn), 1) == UNSPEC_CONSTTABLE) + { + insn_pseudo_needed = TRUE; + break; + } + /* Fall through. */ + case JUMP_INSN: + case CALL_INSN: + case JUMP_TABLE_DATA: + insn_pseudo_needed = FALSE; + break; + case CODE_LABEL: + if (insn_pseudo_needed) + { + emit_insn_after (gen_insn_pseudo (), insn); + insn_pseudo_needed = FALSE; + } + break; + default: + break; + } +} + /* Implement TARGET_MACHINE_DEPENDENT_REORG. */ static void @@ -19050,6 +19092,7 @@ mips_machine_reorg2 (void) optimizations, but this should be an extremely rare case anyhow. */ mips_reorg_process_insns (); mips16_split_long_branches (); + mips_insert_insn_pseudos (); return 0; } diff --git a/gcc/config/mips/mips.md b/gcc/config/mips/mips.md index d8d564fabd9..b7e8e96820d 100644 --- a/gcc/config/mips/mips.md +++ b/gcc/config/mips/mips.md @@ -120,6 +120,7 @@ ;; MIPS16 constant pools. UNSPEC_ALIGN + UNSPEC_CONSTTABLE UNSPEC_CONSTTABLE_INT UNSPEC_CONSTTABLE_FLOAT @@ -151,6 +152,9 @@ ;; Stack checking. UNSPEC_PROBE_STACK_RANGE + + ;; The `.insn' pseudo-op. + UNSPEC_INSN_PSEUDO ]) (define_constants @@ -7174,6 +7178,14 @@ return "#nop"; } [(set_attr "type" "nop")]) + +;; The `.insn' pseudo-op. +(define_insn "insn_pseudo" + [(unspec_volatile [(const_int 0)] UNSPEC_INSN_PSEUDO)] + "" + ".insn" + [(set_attr "mode" "none") + (set_attr "insn_count" "0")]) ;; MIPS4 Conditional move instructions. @@ -7308,6 +7320,13 @@ ;; .................... ;; +(define_insn "consttable" + [(unspec_volatile [(const_int 0)] UNSPEC_CONSTTABLE)] + "" + "" + [(set_attr "mode" "none") + (set_attr "insn_count" "0")]) + (define_insn "consttable_tls_reloc" [(unspec_volatile [(match_operand 0 "tls_reloc_operand" "") (match_operand 1 "const_int_operand" "")] diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index e7e78506ef2..e0c99bf50a2 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,12 @@ +2016-11-15 Maciej W. Rozycki + + * gcc.target/mips/insn-casesi.c: New test case. + * gcc.target/mips/insn-pseudo-1.c: New test case. + * gcc.target/mips/insn-pseudo-2.c: New test case. + * gcc.target/mips/insn-pseudo-3.c: New test case. + * gcc.target/mips/insn-pseudo-4.c: New test case. + * gcc.target/mips/insn-tablejump.c: New test case. + 2016-11-15 Maciej W. Rozycki * gcc.target/mips/mips.exp (mips_option_tests): Add diff --git a/gcc/testsuite/gcc.target/mips/insn-casesi.c b/gcc/testsuite/gcc.target/mips/insn-casesi.c new file mode 100644 index 00000000000..2b4c9f21986 --- /dev/null +++ b/gcc/testsuite/gcc.target/mips/insn-casesi.c @@ -0,0 +1,112 @@ +/* { dg-do run } */ +/* { dg-options "-mips16 -mcode-readable=yes" } */ + +int __attribute__ ((noinline)) +frob (int i) +{ + switch (i) + { + case -5: + return -2; + case -3: + return -1; + case 0: + return 0; + case 3: + return 1; + case 5: + break; + default: + __builtin_unreachable (); + } + return i; +} + +int +main (int argc, char **argv) +{ + asm ("" : "+r" (argc)); + argc = frob ((argc & 10) - 5); + asm ("" : "+r" (argc)); + return !argc; +} + +/* This will result in assembly like: + + .text + .align 2 + .globl frob + .set mips16 + .set nomicromips + .ent frob + .type frob, @function +frob: + .frame $sp,0,$31 # vars= 0, regs= 0/0, args= 0, gp= 0 + .mask 0x00000000,0 + .fmask 0x00000000,0 + addiu $2,$4,5 + sltu $2,11 + bteqz $L2 + sll $3,$2,1 + la $2,$L4 + addu $3,$2,$3 + lh $3,0($3) + addu $2,$2,$3 + j $2 + .align 1 + .align 2 +$L4: + .half $L3-$L4 + .half $L2-$L4 + .half $L9-$L4 + .half $L2-$L4 + .half $L2-$L4 + .half $L8-$L4 + .half $L2-$L4 + .half $L2-$L4 + .half $L7-$L4 + .half $L2-$L4 + .half $L8-$L4 +$L8: + .set noreorder + .set nomacro + jr $31 + move $2,$4 + .set macro + .set reorder + +$L9: + li $2,1 + .set noreorder + .set nomacro + jr $31 + neg $2,$2 + .set macro + .set reorder + +$L3: + li $2,2 + .set noreorder + .set nomacro + jr $31 + neg $2,$2 + .set macro + .set reorder + +$L7: + .set noreorder + .set nomacro + jr $31 + li $2,1 + .set macro + .set reorder + +$L2: + .insn + .end frob + .size frob, .-frob + + for `frob' and we want to make sure it links correctly owing to the + `.insn' pseudo-op which needs to be there at `$L2' as there's no + code following and the label is a MIPS16 branch target (even though + the branch is never taken. See also insn-tablejump.c. */ diff --git a/gcc/testsuite/gcc.target/mips/insn-pseudo-1.c b/gcc/testsuite/gcc.target/mips/insn-pseudo-1.c new file mode 100644 index 00000000000..42501952f9c --- /dev/null +++ b/gcc/testsuite/gcc.target/mips/insn-pseudo-1.c @@ -0,0 +1,23 @@ +/* { dg-do compile } */ +/* { dg-options "-mno-micromips -mno-mips16" } */ + +void +unreachable (int i) +{ + asm volatile goto ("b\t.\n\tbeqz\t%0,%l1" : : "r" (i) : : punt); +punt: + __builtin_unreachable (); +} + +/* Expect assembly like: + + beqz $4,$L2 + # Anything goes here. +$L2: # The label must match. + .insn +$L3 = . # It's there, but we don't care. + .end unreachable + + that is .insn to be inserted if a code label is at function's end. */ + +/* { dg-final { scan-assembler "\tbeqz\t\\\$\[0-9\]+,(.L\[0-9\]+)\n.*\n\\1:\n\t\\.insn\n(?:.L\[0-9\]+ = \\.\n)?\t\\.end\tunreachable\n" } } */ diff --git a/gcc/testsuite/gcc.target/mips/insn-pseudo-2.c b/gcc/testsuite/gcc.target/mips/insn-pseudo-2.c new file mode 100644 index 00000000000..81fb2596230 --- /dev/null +++ b/gcc/testsuite/gcc.target/mips/insn-pseudo-2.c @@ -0,0 +1,23 @@ +/* { dg-do compile } */ +/* { dg-options "-mmicromips" } */ + +void +unreachable (int i) +{ + asm volatile goto ("b\t.\n\tbeqz\t%0,%l1" : : "r" (i) : : punt); +punt: + __builtin_unreachable (); +} + +/* Expect assembly like: + + beqz $4,$L2 + # Anything goes here. +$L2: # The label must match. + .insn +$L3 = . # It's there, but we don't care. + .end unreachable + + that is .insn to be inserted if a code label is at function's end. */ + +/* { dg-final { scan-assembler "\tbeqz\t\\\$\[0-9\]+,(.L\[0-9\]+)\n.*\n\\1:\n\t\\.insn\n(?:.L\[0-9\]+ = \\.\n)?\t\\.end\tunreachable\n" } } */ diff --git a/gcc/testsuite/gcc.target/mips/insn-pseudo-3.c b/gcc/testsuite/gcc.target/mips/insn-pseudo-3.c new file mode 100644 index 00000000000..49b7622ba78 --- /dev/null +++ b/gcc/testsuite/gcc.target/mips/insn-pseudo-3.c @@ -0,0 +1,23 @@ +/* { dg-do compile } */ +/* { dg-options "-mips16" } */ + +void +unreachable (int i) +{ + asm volatile goto ("b\t.\n\tbeqz\t%0,%l1" : : "r" (i) : : punt); +punt: + __builtin_unreachable (); +} + +/* Expect assembly like: + + beqz $4,$L2 + # Anything goes here. +$L2: # The label must match. + .insn +$L3 = . # It's there, but we don't care. + .end unreachable + + that is .insn to be inserted if a code label is at function's end. */ + +/* { dg-final { scan-assembler "\tbeqz\t\\\$\[0-9\]+,(.L\[0-9\]+)\n.*\n\\1:\n\t\\.insn\n(?:.L\[0-9\]+ = \\.\n)?\t\\.end\tunreachable\n" } } */ diff --git a/gcc/testsuite/gcc.target/mips/insn-pseudo-4.c b/gcc/testsuite/gcc.target/mips/insn-pseudo-4.c new file mode 100644 index 00000000000..49a48519161 --- /dev/null +++ b/gcc/testsuite/gcc.target/mips/insn-pseudo-4.c @@ -0,0 +1,27 @@ +/* { dg-do compile } */ +/* { dg-options "-mips16 -mcode-readable=yes" } */ + +void +unreachable (void) +{ + asm volatile goto ("b\t.\n\tbeqz\t%0,%l1" : : "r" (0x12345678) : : punt); +punt: + __builtin_unreachable (); +} + +/* Expect assembly like: + + lw $2,$L5 + # Anything goes here. + beqz $2,$L2 # The register must match. + # Anything goes here. +$L2: # The label must match. + .insn +$L3 = . # It's there, but we don't care. + .align 2 +$L5: # The label must match. + .word 305419896 + + that is .insn to be inserted if a code label is at a constant pool. */ + +/* { dg-final { scan-assembler "\tlw\t(\\\$\[0-9\]+),(.L\[0-9\]+)\n.*\tbeqz\t\\1,(.L\[0-9\]+)\n.*\n\\3:\n\t\\.insn\n(?:.L\[0-9\]+ = \\.\n)?\t\\.align\t2\n\\2:\n\t\\.word\t305419896\n" } } */ diff --git a/gcc/testsuite/gcc.target/mips/insn-tablejump.c b/gcc/testsuite/gcc.target/mips/insn-tablejump.c new file mode 100644 index 00000000000..ecba154b9e0 --- /dev/null +++ b/gcc/testsuite/gcc.target/mips/insn-tablejump.c @@ -0,0 +1,98 @@ +/* { dg-do run } */ +/* { dg-options "-mmicromips" } */ + +int __attribute__ ((noinline)) +frob (int i) +{ + switch (i) + { + case -5: + return -2; + case -3: + return -1; + case 0: + return 0; + case 3: + return 1; + case 5: + break; + default: + __builtin_unreachable (); + } + return i; +} + +int +main (int argc, char **argv) +{ + asm ("" : "+r" (argc)); + argc = frob ((argc & 10) - 5); + asm ("" : "+r" (argc)); + return !argc; +} + +/* This will result in assembly like: + + .text + .align 2 + .globl frob + .set nomips16 + .set micromips + .ent frob + .type frob, @function +frob: + .frame $sp,0,$31 # vars= 0, regs= 0/0, args= 0, gp= 0 + .mask 0x00000000,0 + .fmask 0x00000000,0 + .set noreorder + .set nomacro + addiu $3,$4,5 + sltu $2,$3,11 + beqzc $2,$L2 + lui $2,%hi($L4) + addiu $2,$2,%lo($L4) + lwxs $3,$3($2) + jrc $3 + .rdata + .align 2 + .align 2 +$L4: + .word $L3 + .word $L2 + .word $L9 + .word $L2 + .word $L2 + .word $L8 + .word $L2 + .word $L2 + .word $L7 + .word $L2 + .word $L8 + .text +$L8: + jr $31 + move $2,$4 + +$L9: + jr $31 + li $2,-1 # 0xffffffffffffffff + +$L3: + jr $31 + li $2,-2 # 0xfffffffffffffffe + +$L7: + jr $31 + li $2,1 # 0x1 + +$L2: + .insn + .set macro + .set reorder + .end frob + .size frob, .-frob + + for `frob' and we want to make sure it links correctly owing to the + `.insn' pseudo-op which needs to be there at `$L2' as there's no + code following and the label is a microMIPS branch target (even though + the branch is never taken. See also insn-casesi.c. */ -- 2.30.2