From 9736d8f03364068c9ca786f88a4c2881d98d5768 Mon Sep 17 00:00:00 2001 From: Brian Paul Date: Mon, 5 Jan 2009 13:12:12 -0700 Subject: [PATCH] mesa: fix a GLSL swizzled writemask bug This fixes cases such as: vec4 v4; vec2 v2; v4.xz.yx = v2; The last line now correctly compiles into MOV TEMP[1].xz, TEMP[0].yyxw; Helps to fix the Humus Domino demo. See bug 19189. --- src/mesa/shader/slang/slang_codegen.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) diff --git a/src/mesa/shader/slang/slang_codegen.c b/src/mesa/shader/slang/slang_codegen.c index 4976daf533b..8e28be8abd1 100644 --- a/src/mesa/shader/slang/slang_codegen.c +++ b/src/mesa/shader/slang/slang_codegen.c @@ -3322,6 +3322,22 @@ is_store_writable(const slang_assemble_ctx *A, const slang_ir_storage *store) } +/** + * Walk up an IR storage path to compute the final swizzle. + * This is used when we find an expression such as "foo.xz.yx". + */ +static GLuint +root_swizzle(const slang_ir_storage *st) +{ + GLuint swizzle = st->Swizzle; + while (st->Parent) { + st = st->Parent; + swizzle = _slang_swizzle_swizzle(st->Swizzle, swizzle); + } + return swizzle; +} + + /** * Generate IR tree for an assignment (=). */ @@ -3397,9 +3413,9 @@ _slang_gen_assignment(slang_assemble_ctx * A, slang_operation *oper) rhs = _slang_gen_operation(A, &oper->children[1]); if (lhs && rhs) { /* convert lhs swizzle into writemask */ + const GLuint swizzle = root_swizzle(lhs->Store); GLuint writemask, newSwizzle; - if (!swizzle_to_writemask(A, lhs->Store->Swizzle, - &writemask, &newSwizzle)) { + if (!swizzle_to_writemask(A, swizzle, &writemask, &newSwizzle)) { /* Non-simple writemask, need to swizzle right hand side in * order to put components into the right place. */ -- 2.30.2