Shift Operators

The right shift argument can be any integer or Ivec value, and is implicitly converted to a M64 data type. The first or left operand of a << can be of any type except I[s|u]8vec[8|16]

Example Syntax Usage for Shift Operators

/* Automatic size and sign conversion */

Is16vec4 A,C;

Iu32vec2 B;

C = A;

/* A&B returns I16vec4, which must be cast to Iu16vec4

to ensure logical shift, not arithmetic shift */

Is16vec4 A, C;

Iu16vec4 B, R;

R = (Iu16vec4)(A & B) C;

/* A&B returns I16vec4, which must be cast to Is16vec4

to ensure arithmetic shift, not logical shift */

R = (Is16vec4)(A & B) C;

Shift Operators with Corresponding Intrinsics

Operation	Symbols	Syntax Usage	Intrinsic
Shift Left	<< &=	R = A << B R &= A	_mm_sll_si64 _mm_slli_si64 _mm_sll_pi32 _mm_slli_pi32 _mm_sll_pi16 _mm_slli_pi16
Shift Right	>>	R = A >> B R >>= A	_mm_srl_si64 _mm_srli_si64 _mm_srl_pi32 _mm_srli_pi32 _mm_srl_pi16 _mm_srli_pi16 _mm_sra_pi32 _mm_srai_pi32 _mm_sra_pi16 _mm_srai_pi16

Right shift operations with signed data types use arithmetic shifts. All unsigned and intermediate classes correspond to logical shifts. The table below shows how the return type is determined by the first argument type.

Shift Operator Overloading

Operation	R	Right Shift		Left Shift		A	B
Logical	I64vec1	>>	>>=	<<	<<=	I64vec1 A;	I64vec1 B;
Logical	I32vec2	>>	>>=	<<	<<=	I32vec2 A	I32vec2 B;
Arithmetic	Is32vec2	>>	>>=	<<	<<=	Is32vec2 A	I[s\|u][N]vec[N] B;
Logical	Iu32vec2	>>	>>=	<<	<<=	Iu32vec2 A	I[s\|u][N]vec[N] B;
Logical	I16vec4	>>	>>=	<<	<<=	I16vec4 A	I16vec4 B
Arithmetic	Is16vec4	>>	>>=	<<	<<=	Is16vec4 A	I[s\|u][N]vec[N] B;
Logical	Iu16vec4	>>	>>=	<<	<<=	Iu16vec4 A	I[s\|u][N]vec[N] B;