diff options
| -rw-r--r-- | src/compiler/glsl/ir_constant_expression.cpp | 40 |
1 files changed, 27 insertions, 13 deletions
diff --git a/src/compiler/glsl/ir_constant_expression.cpp b/src/compiler/glsl/ir_constant_expression.cpp index 01a7224f470..a70c6600f5a 100644 --- a/src/compiler/glsl/ir_constant_expression.cpp +++ b/src/compiler/glsl/ir_constant_expression.cpp @@ -477,6 +477,23 @@ ir_rvalue::constant_expression_value(struct hash_table *) return NULL; } +static uint32_t +bitfield_reverse(uint32_t v) +{ + /* http://graphics.stanford.edu/~seander/bithacks.html#BitReverseObvious */ + uint32_t r = v; // r will be reversed bits of v; first get LSB of v + int s = sizeof(v) * CHAR_BIT - 1; // extra shift needed at end + + for (v >>= 1; v; v >>= 1) { + r <<= 1; + r |= v & 1; + s--; + } + r <<= s; // shift when v's highest bits are zero + + return r; +} + ir_constant * ir_expression::constant_expression_value(struct hash_table *variable_context) { @@ -1482,20 +1499,17 @@ ir_expression::constant_expression_value(struct hash_table *variable_context) break; case ir_unop_bitfield_reverse: - /* http://graphics.stanford.edu/~seander/bithacks.html#BitReverseObvious */ - for (unsigned c = 0; c < components; c++) { - unsigned int v = op[0]->value.u[c]; // input bits to be reversed - unsigned int r = v; // r will be reversed bits of v; first get LSB of v - int s = sizeof(v) * CHAR_BIT - 1; // extra shift needed at end - - for (v >>= 1; v; v >>= 1) { - r <<= 1; - r |= v & 1; - s--; + for (unsigned c = 0; c < op[0]->type->components(); c++) { + switch (this->type->base_type) { + case GLSL_TYPE_UINT: + data.u[c] = bitfield_reverse(op[0]->value.u[c]); + break; + case GLSL_TYPE_INT: + data.i[c] = bitfield_reverse(op[0]->value.i[c]); + break; + default: + assert(0); } - r <<= s; // shift when v's highest bits are zero - - data.u[c] = r; } break; |