From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1666) id 07B173857709; Fri, 13 Oct 2023 06:34:52 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 07B173857709 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1697178892; bh=wY4/6xwhdjUMyW9+moN7SwaNruGsolzRUV1cZlamoe0=; h=From:To:Subject:Date:From; b=XWLwAWX5rilVkNraDRND2YcHBMCu1XmtGhwfjkGomp0tgxQV7nIXhNbnLmgYpHMzn DjjcDC171SQEYieHpVx7ygHvHtwh9Ujy1j6jojBQQrBtn6PIwVJcSbUmNj4VMQQ5Uu woaqPyNZE69QCva1B+V+cZ5NPsqIYUVjsHEDPJrE= MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="utf-8" From: Richard Biener To: gcc-cvs@gcc.gnu.org Subject: [gcc r14-4612] tree-optimization/111779 - Handle some BIT_FIELD_REFs in SRA X-Act-Checkin: gcc X-Git-Author: Richard Biener X-Git-Refname: refs/heads/master X-Git-Oldrev: 35b5bb475375dba4ea9101d6db13a6012c4e84ca X-Git-Newrev: 6decda1a35be5764101987c210b5693a0d914e58 Message-Id: <20231013063452.07B173857709@sourceware.org> Date: Fri, 13 Oct 2023 06:34:52 +0000 (GMT) List-Id: https://gcc.gnu.org/g:6decda1a35be5764101987c210b5693a0d914e58 commit r14-4612-g6decda1a35be5764101987c210b5693a0d914e58 Author: Richard Biener Date: Thu Oct 12 11:34:57 2023 +0200 tree-optimization/111779 - Handle some BIT_FIELD_REFs in SRA The following handles byte-aligned, power-of-two and byte-multiple sized BIT_FIELD_REF reads in SRA. In particular this should cover BIT_FIELD_REFs created by optimize_bit_field_compare. For gcc.dg/tree-ssa/ssa-dse-26.c we now SRA the BIT_FIELD_REF appearing there leading to more DSE, fully eliding the aggregates. This results in the same false positive -Wuninitialized as the older attempt to remove the folding from optimize_bit_field_compare, fixed by initializing part of the aggregate unconditionally. PR tree-optimization/111779 gcc/ * tree-sra.cc (sra_handled_bf_read_p): New function. (build_access_from_expr_1): Handle some BIT_FIELD_REFs. (sra_modify_expr): Likewise. (make_fancy_name_1): Skip over BIT_FIELD_REF. gcc/fortran/ * trans-expr.cc (gfc_trans_assignment_1): Initialize lhs_caf_attr and rhs_caf_attr codimension flag to avoid false positive -Wuninitialized. gcc/testsuite/ * gcc.dg/tree-ssa/ssa-dse-26.c: Adjust for more DSE. * gcc.dg/vect/vect-pr111779.c: New testcase. Diff: --- gcc/fortran/trans-expr.cc | 5 ++- gcc/testsuite/gcc.dg/tree-ssa/ssa-dse-26.c | 4 +-- gcc/testsuite/gcc.dg/vect/vect-pr111779.c | 56 ++++++++++++++++++++++++++++++ gcc/tree-sra.cc | 24 +++++++++++-- 4 files changed, 83 insertions(+), 6 deletions(-) diff --git a/gcc/fortran/trans-expr.cc b/gcc/fortran/trans-expr.cc index 7beefa2e69c..1b8be081a17 100644 --- a/gcc/fortran/trans-expr.cc +++ b/gcc/fortran/trans-expr.cc @@ -12015,7 +12015,10 @@ gfc_trans_assignment_1 (gfc_expr * expr1, gfc_expr * expr2, bool init_flag, && !is_runtime_conformable (expr1, expr2); /* Only analyze the expressions for coarray properties, when in coarray-lib - mode. */ + mode. Avoid false-positive uninitialized diagnostics with initializing + the codimension flag unconditionally. */ + lhs_caf_attr.codimension = false; + rhs_caf_attr.codimension = false; if (flag_coarray == GFC_FCOARRAY_LIB) { lhs_caf_attr = gfc_caf_attr (expr1, false, &lhs_refs_comp); diff --git a/gcc/testsuite/gcc.dg/tree-ssa/ssa-dse-26.c b/gcc/testsuite/gcc.dg/tree-ssa/ssa-dse-26.c index e3c33f49ef6..43152de5616 100644 --- a/gcc/testsuite/gcc.dg/tree-ssa/ssa-dse-26.c +++ b/gcc/testsuite/gcc.dg/tree-ssa/ssa-dse-26.c @@ -31,5 +31,5 @@ constraint_equal (struct constraint a, struct constraint b) && constraint_expr_equal (a.rhs, b.rhs); } -/* { dg-final { scan-tree-dump-times "Deleted dead store: x = " 1 "dse1" } } */ -/* { dg-final { scan-tree-dump-times "Deleted dead store: y = " 1 "dse1" } } */ +/* { dg-final { scan-tree-dump-times "Deleted dead store: x = " 2 "dse1" } } */ +/* { dg-final { scan-tree-dump-times "Deleted dead store: y = " 2 "dse1" } } */ diff --git a/gcc/testsuite/gcc.dg/vect/vect-pr111779.c b/gcc/testsuite/gcc.dg/vect/vect-pr111779.c new file mode 100644 index 00000000000..79b72aebc78 --- /dev/null +++ b/gcc/testsuite/gcc.dg/vect/vect-pr111779.c @@ -0,0 +1,56 @@ +#include +#include "tree-vect.h" + +struct C +{ + int c; + int d; + bool f :1; + float e; +}; + +struct A +{ + unsigned int a; + unsigned char c1, c2; + bool b1 : 1; + bool b2 : 1; + bool b3 : 1; + struct C b4; +}; + +void __attribute__((noipa)) +foo (const struct A * __restrict x, int y) +{ + int s = 0, i = 0; + for (i = 0; i < y; ++i) + { + const struct A a = x[i]; + s += a.b4.f ? 1 : 0; + } + if (s != 0) + __builtin_abort (); +} + +int +main () +{ + struct A x[100]; + int i; + + check_vect (); + + __builtin_memset (x, -1, sizeof (x)); +#pragma GCC novect + for (i = 0; i < 100; i++) + { + x[i].b1 = false; + x[i].b2 = false; + x[i].b3 = false; + x[i].b4.f = false; + } + foo (x, 100); + return 0; +} + +/* { dg-final { scan-tree-dump "LOOP VECTORIZED" "vect" { target vect_int } } } */ diff --git a/gcc/tree-sra.cc b/gcc/tree-sra.cc index 56a8ba26135..24d0c20da6a 100644 --- a/gcc/tree-sra.cc +++ b/gcc/tree-sra.cc @@ -1113,6 +1113,21 @@ disqualify_base_of_expr (tree t, const char *reason) disqualify_candidate (t, reason); } +/* Return true if the BIT_FIELD_REF read EXPR is handled by SRA. */ + +static bool +sra_handled_bf_read_p (tree expr) +{ + uint64_t size, offset; + if (bit_field_size (expr).is_constant (&size) + && bit_field_offset (expr).is_constant (&offset) + && size % BITS_PER_UNIT == 0 + && offset % BITS_PER_UNIT == 0 + && pow2p_hwi (size)) + return true; + return false; +} + /* Scan expression EXPR and create access structures for all accesses to candidates for scalarization. Return the created access or NULL if none is created. */ @@ -1123,7 +1138,8 @@ build_access_from_expr_1 (tree expr, gimple *stmt, bool write) struct access *ret = NULL; bool partial_ref; - if (TREE_CODE (expr) == BIT_FIELD_REF + if ((TREE_CODE (expr) == BIT_FIELD_REF + && (write || !sra_handled_bf_read_p (expr))) || TREE_CODE (expr) == IMAGPART_EXPR || TREE_CODE (expr) == REALPART_EXPR) { @@ -1170,6 +1186,7 @@ build_access_from_expr_1 (tree expr, gimple *stmt, bool write) case COMPONENT_REF: case ARRAY_REF: case ARRAY_RANGE_REF: + case BIT_FIELD_REF: ret = create_access (expr, stmt, write); break; @@ -1549,6 +1566,7 @@ make_fancy_name_1 (tree expr) obstack_grow (&name_obstack, buffer, strlen (buffer)); break; + case BIT_FIELD_REF: case ADDR_EXPR: make_fancy_name_1 (TREE_OPERAND (expr, 0)); break; @@ -1564,7 +1582,6 @@ make_fancy_name_1 (tree expr) } break; - case BIT_FIELD_REF: case REALPART_EXPR: case IMAGPART_EXPR: gcc_unreachable (); /* we treat these as scalars. */ @@ -3769,7 +3786,8 @@ sra_modify_expr (tree *expr, gimple_stmt_iterator *gsi, bool write) tree type, bfr, orig_expr; bool partial_cplx_access = false; - if (TREE_CODE (*expr) == BIT_FIELD_REF) + if (TREE_CODE (*expr) == BIT_FIELD_REF + && (write || !sra_handled_bf_read_p (*expr))) { bfr = *expr; expr = &TREE_OPERAND (*expr, 0);