C. OpenMP C 和 C++ 文法

C.1 標記法
C.2 規則

C.1 標記法

文法規則包含非終端機的名稱，後面接著冒號，後面接著個別行的取代替代項目。

語法運算式字詞 _opt 表示字詞在取代中是選擇性的。

語法運算式字詞_optseq 相當於 term-seq_opt，具有下列額外規則：

term-seq：
 term
 term-seq term
 term-seq , term

C.2 規則

C 標準的第 6.1 節會說明標記法。 此文法附錄顯示 OpenMP C 和 C++ 指示詞基底語言文法的延伸模組。

/* 在 C++ (ISO/IEC 14882:1998) */

statement-seq：
 陳述式
 openmp-directive
 statement-seq 陳述式
 statement-seq openmp-directive

/* 在 C90 (ISO/IEC 9899:1990) */

statement-list:
 陳述式
 openmp-directive
 statement-list statement
 statement-list openmp-directive

/* 在 C99 (ISO/IEC 9899:1999) */

block-item：
 宣告
 陳述式
 openmp-directive

/* 標準陳述式 */

statement:
 openmp-construct

openmp-construct：
 parallel-construct
 for-construct
 sections-construct
 single-construct
 parallel-for-construct
 parallel-sections-construct
 master-construct
 critical-construct
 atomic-construct
 ordered-construct

openmp-directive：
 barrier-directive
 flush-directive

structured-block：
 陳述式

parallel-construct：
 parallel-directive structured-block

parallel-directive：
  # pragma omp parallel parallel-clause_optseq new-line

parallel-clause：
 unique-parallel-clause
 data-clause

unique-parallel-clause：
  if ( expression )
  num_threads ( expression )

for-construct：
 for-directive iteration-statement

for-directive：
  # pragma omp for for-clause_optseq new-line

for-clause：
 unique-for-clause
 data-clause
  nowait

unique-for-clause：
  ordered
  schedule ( schedule-kind )
  schedule ( schedule-kind , expression )

schedule-kind：
  static
  dynamic
  guided
  runtime

sections-construct：
 sections-directive section-scope

sections-directive：
  # pragma omp sections sections-clause_optseq new-line

sections-clause：
 data-clause
  nowait

section-scope：
 { section-sequence }

section-sequence：
 section-directive_opt structured-block
 section-sequence section-directive structured-block

section-directive：
  # pragma omp section new-line

single-construct：
 single-directive structured-block

single-directive：
  # pragma omp single single-clause_optseq new-line

single-clause：
 data-clause
  nowait

parallel-for-construct：
 parallel-for-directive iteration-statement

parallel-for-directive：
  # pragma omp parallel for parallel-for-clause_optseq new-line

parallel-for-clause：
 unique-parallel-clause
 unique-for-clause
 data-clause

parallel-sections-construct：
 parallel-sections-directive section-scope

parallel-sections-directive：
  # pragma omp parallel sections parallel-sections-clause_optseq new-line

parallel-sections-clause：
 unique-parallel-clause
 data-clause

master-construct：
 master-directive structured-block

master-directive：
  # pragma omp master new-line

critical-construct：
 critical-directive structured-block

critical-directive：
  # pragma omp critical region-phrase_opt new-line

region-phrase：
 (identifier)

barrier-directive：
  # pragma omp barrier new-line

atomic-construct：
 atomic-directive expression-statement

atomic-directive：
  # pragma omp atomic new-line

flush-directive：
  # pragma omp flush flush-vars_opt new-line

flush-vars：
 (variable-list)

ordered-construct：
 ordered-directive structured-block

ordered-directive：
  # pragma omp ordered new-line

/* 標準宣告 */

declaration：
 threadprivate-directive

threadprivate-directive：
  # pragma omp threadprivate ( variable-list ) new-line

data-clause：
  private ( variable-list )
  copyprivate ( variable-list )
  firstprivate ( variable-list )
  lastprivate ( variable-list )
  shared ( variable-list )
  default ( shared )
  default ( none )
  reduction ( reduction-operator : variable-list )
  copyin ( variable-list )

reduction-operator：
 其中一個：+ \* - & ^ | && ||

/* 在 C */

variable-list：
 識別碼
 variable-list , identifier

/* 在 C++ */

variable-list：
 id-expression
 variable-list , id-expression