// Input domain for the Structured ExecutionShape generator stage
// (loom-raise-opt --loom-materialize-fmuladd=shape=...).
//
// The generator consumes a finite set of exact Structured Program references
// (linked-input-61), so each sample is a finite module holding one to four
// complete Structured parents (callables).  Two parent shapes are sampled:
//
//   * parents with no unresolved selected-Spatial execution-shape choice,
//     which the generator must pass through unchanged (linked-input-61);
//   * parents holding one or more unresolved, exactly representable
//     `llvm.intr.fmuladd` operations (linked-input-101, linked-input-127).
//
// Exact representability is an input well-formedness requirement of the
// sampled claim, so every sampled callable states only a floating environment
// the standard `math`/`arith` spellings can restate: either no floating
// attribute at all, or the ordinary non-constrained Clang envelope
// (`fp_contract = "off"`, IEEE denormal environment, code-generation-only
// passthrough strings, `no-trapping-math = "true"`).  Operand and result
// types stay exact standard numeric types (floats and fixed-shape vectors of
// floats).
//
// One execution-shape decision applies uniformly to every unresolved fmuladd
// of a complete parent (linked-input-165), so the shape itself is a single
// subject-command option and is never sampled per operation here.  The
// grammar samples only inputs: it never spells math.fma, arith.mulf or
// arith.addf as an expected result.
//
// Nested callables are sampled too (linked-input-165 names operations owned
// by nested callables), as a native func.func parent holding an inner
// imported llvm.func.

start: {new COUNT = random.randint(1, 4); new I = 0}
       parents;

parents: (I < COUNT) parent {I += 1} parents
       | (I == COUNT) '';

parent: plain_fma_func
      | typed_fma_func
      | envelope_fma_func
      | mixed_fma_func
      | native_fma_func
      | nested_callable_func
      | no_choice_func;

// ------------------------------------------------------- unresolved parents

// An imported callable stating no floating-point environment of its own.
plain_fma_func: {new NAME = 'plain_' + str(I); new TY = 'f32'; new N = random.randint(1, 3); new K = 0; new SRC = '%x'; new FM = ''}
  'llvm.func @' [NAME] '(%x: ' [TY] ', %y: ' [TY] ', %z: ' [TY] ') -> ' [TY] ' {\n'
  fma_chain
  '  llvm.return ' [SRC] ' : ' [TY] '\n'
  '}\n\n';

// The exact floating type and fast-math contract are part of the sampled
// input (linked-input-101), so both vary over exact standard numeric types
// and over the imported fast-math flag sets.
typed_fma_func: {new NAME = 'typed_' + str(I); new TY = random.choice(['f32', 'f64', 'f16', 'vector<4xf32>', 'vector<8xf64>']); new N = random.randint(1, 3); new K = 0; new SRC = '%x'; new FM = ''}
  fastmath_choice
  'llvm.func @' [NAME] '(%x: ' [TY] ', %y: ' [TY] ', %z: ' [TY] ') -> ' [TY] ' {\n'
  fma_chain
  '  llvm.return ' [SRC] ' : ' [TY] '\n'
  '}\n\n';

// An ordinary Clang function envelope that states no environment a standard
// operation cannot restate: the choice is still unresolved and representable.
envelope_fma_func: {new NAME = 'envelope_' + str(I); new TY = random.choice(['f32', 'f64']); new N = random.randint(1, 2); new K = 0; new SRC = '%x'; new FM = ''}
  fastmath_choice
  'llvm.func @' [NAME] '(%x: ' [TY] ', %y: ' [TY] ', %z: ' [TY] ') -> ' [TY] '\n'
  '    attributes {' benign_envelope '} {\n'
  fma_chain
  '  llvm.return ' [SRC] ' : ' [TY] '\n'
  '}\n\n';

// A parent whose selected-Spatial ownership also holds ordinary floating and
// integer computation next to the unresolved choice.
mixed_fma_func: {new NAME = 'mixed_' + str(I); new TY = random.choice(['f32', 'f64']); new N = random.randint(1, 2); new K = 0; new SRC = '%x'; new FM = ''}
  'llvm.func @' [NAME] '(%x: ' [TY] ', %y: ' [TY] ', %z: ' [TY] ', %i: i32) -> ' [TY] ' {\n'
  '  %scaled = llvm.fmul %x, %y : ' [TY] '\n'
  '  %counted = llvm.add %i, %i : i32\n'
  fma_chain
  '  %blended = llvm.fadd ' [SRC] ', %scaled : ' [TY] '\n'
  '  llvm.return %blended : ' [TY] '\n'
  '}\n\n';

// A genuinely standard-MLIR-native callable parent.
native_fma_func: {new NAME = 'native_' + str(I); new TY = random.choice(['f32', 'f64']); new N = random.randint(1, 2); new K = 0; new SRC = '%x'; new FM = ''}
  'func.func @' [NAME] '(%x: ' [TY] ', %y: ' [TY] ', %z: ' [TY] ') -> ' [TY] ' {\n'
  fma_chain
  '  return ' [SRC] ' : ' [TY] '\n'
  '}\n\n';

// A native parent owning a nested imported callable: the unresolved choice
// lives in the nested callable's own ownership.
nested_callable_func: {new NAME = 'nested_' + str(I); new TY = 'f32'; new N = random.randint(1, 2); new K = 0; new SRC = '%x'; new FM = ''}
  'func.func @' [NAME] '(%a: ' [TY] ') -> ' [TY] ' {\n'
  '  builtin.module {\n'
  '    llvm.func @inner_' [NAME] '(%x: ' [TY] ', %y: ' [TY] ', %z: ' [TY] ') -> ' [TY] ' {\n'
  fma_chain
  '      llvm.return ' [SRC] ' : ' [TY] '\n'
  '    }\n'
  '  }\n'
  '  return %a : ' [TY] '\n'
  '}\n\n';

// ------------------------------------------------------- unresolved chain

fma_chain: (K < N) fma_stmt {K += 1} fma_chain
         | (K == N) '';

fma_stmt: '  %r' [str(K)] ' = llvm.intr.fmuladd(' [SRC] ', %y, %z)' [FM]
          ' : (' [TY] ', ' [TY] ', ' [TY] ') -> ' [TY] '\n'
          {SRC = '%r' + str(K)};

fastmath_choice: {FM = random.choice(['', ' {fastmathFlags = #llvm.fastmath<contract>}', ' {fastmathFlags = #llvm.fastmath<nnan, contract>}', ' {fastmathFlags = #llvm.fastmath<nnan, ninf, nsz>}', ' {fastmathFlags = #llvm.fastmath<fast>}'])} '';

benign_envelope: 'fp_contract = "off"'
    | 'denormal_fpenv = #llvm.denormal_fpenv<default_output_mode = ieee, default_input_mode = ieee, float_output_mode = ieee, float_input_mode = ieee>'
    | 'passthrough = ["nofree", "norecurse", "nosync", ["min-legal-vector-width", "0"], ["no-trapping-math", "true"], ["stack-protector-buffer-size", "8"], ["target-cpu", "generic-rv64"]]';

// ------------------------------------------- parents with no pending choice

// "A parent with no unresolved selected-Spatial execution-shape choice passes
// through unchanged" (linked-input-61): sampled as callables holding ordinary
// floating computation, an already-fused math.fma, or an already-split
// multiply/add pair, and as an empty module.
no_choice_func: ordinary_func
              | already_fused_func
              | already_split_func
              | empty_parent;

ordinary_func: {new NAME = 'ordinary_' + str(I); new TY = random.choice(['f32', 'f64'])}
  'llvm.func @' [NAME] '(%x: ' [TY] ', %y: ' [TY] ') -> ' [TY] ' {\n'
  '  %sum = llvm.fadd %x, %y : ' [TY] '\n'
  '  llvm.return %sum : ' [TY] '\n'
  '}\n\n';

already_fused_func: {new NAME = 'fused_' + str(I); new TY = random.choice(['f32', 'f64'])}
  'llvm.func @' [NAME] '(%x: ' [TY] ', %y: ' [TY] ', %z: ' [TY] ') -> ' [TY] ' {\n'
  '  %fma = math.fma %x, %y, %z : ' [TY] '\n'
  '  llvm.return %fma : ' [TY] '\n'
  '}\n\n';

already_split_func: {new NAME = 'split_' + str(I); new TY = random.choice(['f32', 'f64'])}
  'llvm.func @' [NAME] '(%x: ' [TY] ', %y: ' [TY] ', %z: ' [TY] ') -> ' [TY] ' {\n'
  '  %prod = arith.mulf %x, %y : ' [TY] '\n'
  '  %sum = arith.addf %prod, %z : ' [TY] '\n'
  '  llvm.return %sum : ' [TY] '\n'
  '}\n\n';

empty_parent: '';