From b67230de635528bfc6d5e66b90f7406eb97eb1c0 Mon Sep 17 00:00:00 2001 From: Jason Ekstrand Date: Fri, 1 Sep 2017 22:30:53 -0700 Subject: [PATCH] intel/fs: Protect opt_algebraic from OOB BROADCAST indices Reviewed-by: Iago Toral Quiroga --- src/intel/compiler/brw_fs.cpp | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-) diff --git a/src/intel/compiler/brw_fs.cpp b/src/intel/compiler/brw_fs.cpp index fdbc6db..c2907bf 100644 --- a/src/intel/compiler/brw_fs.cpp +++ b/src/intel/compiler/brw_fs.cpp @@ -2423,8 +2423,17 @@ fs_visitor::opt_algebraic() progress = true; } else if (inst->src[1].file == IMM) { inst->opcode = BRW_OPCODE_MOV; - inst->src[0] = component(inst->src[0], - inst->src[1].ud); + /* It's possible that the selected component will be too large and + * overflow the register. This can happen if someone does a + * readInvocation() from GLSL or SPIR-V and provides an OOB + * invocationIndex. If this happens and we some how manage + * to constant fold it in and get here, then component() may cause + * us to start reading outside of the VGRF which will lead to an + * assert later. Instead, just let it wrap around if it goes over + * exec_size. + */ + const unsigned comp = inst->src[1].ud & (inst->exec_size - 1); + inst->src[0] = component(inst->src[0], comp); inst->sources = 1; inst->force_writemask_all = true; progress = true; -- 2.7.4