From aa29ea0cd4054b64d9dbc9adba3bfd2db2a86be1 Mon Sep 17 00:00:00 2001 From: Thomas Preud'homme Date: Wed, 24 Sep 2014 08:27:21 +0000 Subject: [PATCH] re PR tree-optimization/63266 (Test regression: gcc.target/sh/pr53568-1.c) 2014-09-24 Thomas Preud'homme gcc/ PR tree-optimization/63266 * tree-ssa-math-opts.c (struct symbolic_number): Add comment about marker for unknown byte value. (MARKER_MASK): New macro. (MARKER_BYTE_UNKNOWN): New macro. (HEAD_MARKER): New macro. (do_shift_rotate): Mark bytes with unknown values due to sign extension when doing an arithmetic right shift. Replace hardcoded mask for marker by new MARKER_MASK macro. (find_bswap_or_nop_1): Likewise and adjust ORing of two symbolic numbers accordingly. gcc/testsuite/ PR tree-optimization/63266 * gcc.dg/optimize-bswapsi-1.c (swap32_d): New bswap pass test. From-SVN: r215546 --- gcc/ChangeLog | 14 ++++++++ gcc/testsuite/ChangeLog | 5 +++ gcc/testsuite/gcc.dg/optimize-bswapsi-1.c | 17 ++++++++- gcc/tree-ssa-math-opts.c | 44 +++++++++++++---------- 4 files changed, 61 insertions(+), 19 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index c227481021c..d5f1b1ba599 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,17 @@ +2014-09-24 Thomas Preud'homme + + PR tree-optimization/63266 + * tree-ssa-math-opts.c (struct symbolic_number): Add comment about + marker for unknown byte value. + (MARKER_MASK): New macro. + (MARKER_BYTE_UNKNOWN): New macro. + (HEAD_MARKER): New macro. + (do_shift_rotate): Mark bytes with unknown values due to sign + extension when doing an arithmetic right shift. Replace hardcoded + mask for marker by new MARKER_MASK macro. + (find_bswap_or_nop_1): Likewise and adjust ORing of two symbolic + numbers accordingly. + 2014-09-24 Alexander Ivchenko Maxim Kuznetsov Anna Tikhonova diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index a3f51b36d7e..69d9b3d12c0 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,8 @@ +2014-09-24 Thomas Preud'homme + + PR tree-optimization/63266 + * gcc.dg/optimize-bswapsi-1.c (swap32_d): New bswap pass test. + 2014-09-24 Zhenqiang Chen * gcc.target/arm/pr63210.c: New test. diff --git a/gcc/testsuite/gcc.dg/optimize-bswapsi-1.c b/gcc/testsuite/gcc.dg/optimize-bswapsi-1.c index ebfca6077b9..580e6e0fee2 100644 --- a/gcc/testsuite/gcc.dg/optimize-bswapsi-1.c +++ b/gcc/testsuite/gcc.dg/optimize-bswapsi-1.c @@ -49,5 +49,20 @@ swap32_c (SItype u) | (((u) & 0x000000ff) << 24)); } -/* { dg-final { scan-tree-dump-times "32 bit bswap implementation found at" 3 "bswap" } } */ +/* This variant comes from gcc.target/sh/pr53568-1.c. It requires to track + which bytes have an unpredictable value (eg. due to sign extension) to + make sure that the final expression have only well defined byte values. */ + +SItype +swap32_d (SItype in) +{ + /* 1x swap.w + 2x swap.b */ + return (((in >> 0) & 0xFF) << 24) + | (((in >> 8) & 0xFF) << 16) + | (((in >> 16) & 0xFF) << 8) + | (((in >> 24) & 0xFF) << 0); +} + +/* { dg-final { scan-tree-dump-times "32 bit bswap implementation found at" 4 "bswap" } } */ /* { dg-final { cleanup-tree-dump "bswap" } } */ diff --git a/gcc/tree-ssa-math-opts.c b/gcc/tree-ssa-math-opts.c index c1c2c82e9ae..3c6e9355fff 100644 --- a/gcc/tree-ssa-math-opts.c +++ b/gcc/tree-ssa-math-opts.c @@ -1603,6 +1603,7 @@ make_pass_cse_sincos (gcc::context *ctxt) consisting of octet sized markers: 0 - target byte has the value 0 + FF - target byte has an unknown value (eg. due to sign extension) 1..size - marker value is the target byte index minus one. To detect permutations on memory sources (arrays and structures), a symbolic @@ -1629,6 +1630,10 @@ struct symbolic_number { }; #define BITS_PER_MARKER 8 +#define MARKER_MASK ((1 << BITS_PER_MARKER) - 1) +#define MARKER_BYTE_UNKNOWN MARKER_MASK +#define HEAD_MARKER(n, size) \ + ((n) & ((uint64_t) MARKER_MASK << (((size) - 1) * BITS_PER_MARKER))) /* The number which the find_bswap_or_nop_1 result should match in order to have a nop. The number is masked according to the size of @@ -1651,7 +1656,8 @@ do_shift_rotate (enum tree_code code, struct symbolic_number *n, int count) { - int size = TYPE_PRECISION (n->type) / BITS_PER_UNIT; + int i, size = TYPE_PRECISION (n->type) / BITS_PER_UNIT; + unsigned head_marker; if (count % BITS_PER_UNIT != 0) return false; @@ -1668,11 +1674,13 @@ do_shift_rotate (enum tree_code code, n->n <<= count; break; case RSHIFT_EXPR: - /* Arithmetic shift of signed type: result is dependent on the value. */ - if (!TYPE_UNSIGNED (n->type) - && (n->n & ((uint64_t) 0xff << ((size - 1) * BITS_PER_MARKER)))) - return false; + head_marker = HEAD_MARKER (n->n, size); n->n >>= count; + /* Arithmetic shift of signed type: result is dependent on the value. */ + if (!TYPE_UNSIGNED (n->type) && head_marker) + for (i = 0; i < count / BITS_PER_MARKER; i++) + n->n |= (uint64_t) MARKER_BYTE_UNKNOWN + << ((size - 1 - i) * BITS_PER_MARKER); break; case LROTATE_EXPR: n->n = (n->n << count) | (n->n >> ((size * BITS_PER_MARKER) - count)); @@ -1878,7 +1886,7 @@ find_bswap_or_nop_1 (gimple stmt, struct symbolic_number *n, int limit) if ((val & tmp) != 0 && (val & tmp) != tmp) return NULL; else if (val & tmp) - mask |= (uint64_t) 0xff << (i * BITS_PER_MARKER); + mask |= (uint64_t) MARKER_MASK << (i * BITS_PER_MARKER); n->n &= mask; } @@ -1892,7 +1900,7 @@ find_bswap_or_nop_1 (gimple stmt, struct symbolic_number *n, int limit) break; CASE_CONVERT: { - int type_size, old_type_size; + int i, type_size, old_type_size; tree type; type = gimple_expr_type (stmt); @@ -1905,11 +1913,10 @@ find_bswap_or_nop_1 (gimple stmt, struct symbolic_number *n, int limit) /* Sign extension: result is dependent on the value. */ old_type_size = TYPE_PRECISION (n->type) / BITS_PER_UNIT; - if (!TYPE_UNSIGNED (n->type) - && type_size > old_type_size - && n->n & ((uint64_t) 0xff << ((old_type_size - 1) - * BITS_PER_MARKER))) - return NULL; + if (!TYPE_UNSIGNED (n->type) && type_size > old_type_size + && HEAD_MARKER (n->n, old_type_size)) + for (i = 0; i < type_size - old_type_size; i++) + n->n |= MARKER_BYTE_UNKNOWN << (type_size - 1 - i); if (type_size < 64 / BITS_PER_MARKER) { @@ -1968,7 +1975,7 @@ find_bswap_or_nop_1 (gimple stmt, struct symbolic_number *n, int limit) if (gimple_assign_rhs1 (source_stmt1) != gimple_assign_rhs1 (source_stmt2)) { - int64_t inc, mask; + int64_t inc; HOST_WIDE_INT off_sub; struct symbolic_number *n_ptr; @@ -2002,15 +2009,15 @@ find_bswap_or_nop_1 (gimple stmt, struct symbolic_number *n, int limit) bigger weight according to target endianness. */ inc = BYTES_BIG_ENDIAN ? off_sub + n2.range - n1.range : off_sub; size = TYPE_PRECISION (n1.type) / BITS_PER_UNIT; - mask = 0xff; if (BYTES_BIG_ENDIAN) n_ptr = &n1; else n_ptr = &n2; - for (i = 0; i < size; i++, inc <<= BITS_PER_MARKER, - mask <<= BITS_PER_MARKER) + for (i = 0; i < size; i++, inc <<= BITS_PER_MARKER) { - if (n_ptr->n & mask) + unsigned marker = + (n_ptr->n >> (i * BITS_PER_MARKER)) & MARKER_MASK; + if (marker && marker != MARKER_BYTE_UNKNOWN) n_ptr->n += inc; } } @@ -2028,7 +2035,8 @@ find_bswap_or_nop_1 (gimple stmt, struct symbolic_number *n, int limit) n->bytepos = n1.bytepos; n->type = n1.type; size = TYPE_PRECISION (n->type) / BITS_PER_UNIT; - for (i = 0, mask = 0xff; i < size; i++, mask <<= BITS_PER_MARKER) + for (i = 0, mask = MARKER_MASK; i < size; + i++, mask <<= BITS_PER_MARKER) { uint64_t masked1, masked2; -- 2.30.2