diff options
| author | Chad Versace <[email protected]> | 2011-02-14 13:22:39 -0800 |
|---|---|---|
| committer | Chad Versace <[email protected]> | 2011-02-15 15:46:12 -0800 |
| commit | 62c8c773334c1b0cdd484997a4ccec8945713f8c (patch) | |
| tree | 68b0571305f048a81baae296f26ecbbf65d0c20f /src/glsl/ir_constant_expression.cpp | |
| parent | f2e9981e43b26ca101b774ea6af1f00617098246 (diff) | |
glsl: Reinstate constant-folding for division by zero
Fixes regression: https://bugs.freedesktop.org/show_bug.cgi?id=34160
Commit e7c1f058d18f62aa4871aec623f994d7b68cb8c1 disabled constant-folding
when division-by-zero occured. This was a mistake, because the spec does
allow division by zero. (From section 5.9 of the GLSL 1.20 spec: Dividing
by zero does not cause an exception but does result in an unspecified
value.)
For floating-point division, the original pre-e7c1f05 behavior is
reinstated.
For integer division, constant-fold 1/0 to 0.
Diffstat (limited to 'src/glsl/ir_constant_expression.cpp')
| -rw-r--r-- | src/glsl/ir_constant_expression.cpp | 42 |
1 files changed, 21 insertions, 21 deletions
diff --git a/src/glsl/ir_constant_expression.cpp b/src/glsl/ir_constant_expression.cpp index 7e00db66eec..2a308489656 100644 --- a/src/glsl/ir_constant_expression.cpp +++ b/src/glsl/ir_constant_expression.cpp @@ -310,13 +310,9 @@ ir_expression::constant_expression_value() break; case ir_unop_rsq: - /* FINISHME: Emit warning when division-by-zero is detected. */ assert(op[0]->type->base_type == GLSL_TYPE_FLOAT); for (unsigned c = 0; c < op[0]->type->components(); c++) { - float s = sqrtf(op[0]->value.f[c]); - if (s == 0) - return NULL; - data.f[c] = 1.0F / s; + data.f[c] = 1.0F / sqrtf(op[0]->value.f[c]); } break; @@ -519,18 +515,20 @@ ir_expression::constant_expression_value() switch (op[0]->type->base_type) { case GLSL_TYPE_UINT: - if (op[1]->value.u[c1] == 0) - return NULL; - data.u[c] = op[0]->value.u[c0] / op[1]->value.u[c1]; + if (op[1]->value.u[c1] == 0) { + data.u[c] = 0; + } else { + data.u[c] = op[0]->value.u[c0] / op[1]->value.u[c1]; + } break; case GLSL_TYPE_INT: - if (op[1]->value.i[c1] == 0) - return NULL; - data.i[c] = op[0]->value.i[c0] / op[1]->value.i[c1]; + if (op[1]->value.i[c1] == 0) { + data.i[c] = 0; + } else { + data.i[c] = op[0]->value.i[c0] / op[1]->value.i[c1]; + } break; case GLSL_TYPE_FLOAT: - if (op[1]->value.f[c1] == 0) - return NULL; data.f[c] = op[0]->value.f[c0] / op[1]->value.f[c1]; break; default: @@ -548,18 +546,20 @@ ir_expression::constant_expression_value() switch (op[0]->type->base_type) { case GLSL_TYPE_UINT: - if (op[1]->value.u[c1] == 0) - return NULL; - data.u[c] = op[0]->value.u[c0] % op[1]->value.u[c1]; + if (op[1]->value.u[c1] == 0) { + data.u[c] = 0; + } else { + data.u[c] = op[0]->value.u[c0] % op[1]->value.u[c1]; + } break; case GLSL_TYPE_INT: - if (op[1]->value.i[c1] == 0) - return NULL; - data.i[c] = op[0]->value.i[c0] % op[1]->value.i[c1]; + if (op[1]->value.i[c1] == 0) { + data.i[c] = 0; + } else { + data.i[c] = op[0]->value.i[c0] % op[1]->value.i[c1]; + } break; case GLSL_TYPE_FLOAT: - if (op[1]->value.f[c1] == 0) - return NULL; /* We don't use fmod because it rounds toward zero; GLSL specifies * the use of floor. */ |