Coverage for src/flag_gems/runtime/backend/_kunlunxin/ops/gelu.py: 0%

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1import logging 

2 

3import triton 

4import triton.language as tl 

5 

6from flag_gems.utils import tl_extra_shim 

7 

8from ..utils.pointwise_dynamic import pointwise_dynamic 

9 

10logger = logging.getLogger("flag_gems").getChild(__name__.lstrip(".")) 

11erf = tl_extra_shim.erf 

12exp = tl_extra_shim.exp 

13pow = tl_extra_shim.pow 

14tanh = tl_extra_shim.tanh 

15 

16 

17@pointwise_dynamic(promotion_methods=[(0, "DEFAULT")]) 

18@triton.jit 

19def gelu_none(x): 

20 scale: tl.constexpr = 0.7071067811 # 1 / math.sqrt(2) 

21 output = 0.5 * x * (1 + erf(x * scale)) 

22 return output 

23 

24 

25@pointwise_dynamic(promotion_methods=[(0, "DEFAULT")]) 

26@triton.jit 

27def gelu_tanh(x): 

28 output = ( 

29 0.5 

30 * x 

31 * (1 + tanh(x * 0.79788456 * (1 + 0.044715 * pow(x.to(tl.float32), 2.0)))) 

32 ) 

33 return output 

34 

35 

36@pointwise_dynamic(promotion_methods=[(0, 1, "DEFAULT")]) 

37@triton.jit 

38def gelu_backward_none(x, dy): 

39 scale1: tl.constexpr = 0.7071067811 # 1 / math.sqrt(2) 

40 scale2: tl.constexpr = 0.3989422803 # 1 / math.sqrt(2 * math.pi) 

41 x_fp32 = x.to(tl.float32) 

42 dydx = ( 

43 scale2 * x_fp32 * tl.exp(-pow(scale1 * x_fp32, 2.0)) 

44 + 0.5 * erf(scale1 * x_fp32) 

45 + 0.5 

46 ) 

47 dx = dydx * dy 

48 return dx 

49 

50 

51@pointwise_dynamic(promotion_methods=[(0, 1, "DEFAULT")]) 

52@triton.jit 

53def gelu_backward_tanh(x, dy): 

54 x_fp32 = x.to(tl.float32) 

55 # 0.79788456 = math.sqrt(2 / math.pi) 

56 tanh_out = tanh(0.79788456 * x * (1 + 0.044715 * pow(x_fp32, 2.0))) 

57 dydx = 0.5 * x * ( 

58 (1 - pow(tanh_out, 2.0)) * (0.79788456 + 0.1070322243 * pow(x_fp32, 2.0)) 

59 ) + 0.5 * (1 + tanh_out) 

60 dx = dydx * dy 

61 return dx 

62 

63 

64def gelu(self, *, approximate="none"): 

65 logger.debug("GEMS GELU FORWARD") 

66 if approximate == "tanh": 

67 out = gelu_tanh(self) 

68 else: 

69 out = gelu_none(self) 

70 return out 

71 

72 

73def gelu_backward(grad_output, self, *, approximate="none"): 

74 logger.debug("GEMS GELU BACKWARD") 

75 if approximate == "tanh": 

76 in_grad = gelu_backward_tanh(self, grad_output) 

77 else: 

78 in_grad = gelu_backward_none(self, grad_output) 

79 return in_grad 

80 

81 

82def gelu_(A, *, approximate="none"): 

83 logger.debug("GEMS GELU_ FORWARD") 

84 if approximate == "tanh": 

85 out = gelu_tanh(A, out0=A) 

86 else: 

87 out = gelu_none(A, out0=A) 

88 return out