From c472568b4e458c9882a98850668f99144c7ca6bf Mon Sep 17 00:00:00 2001 From: Jason Ekstrand Date: Tue, 10 Jan 2017 10:24:55 -0800 Subject: [PATCH] nir/search: Only allow matching SSA values This is more correct and should also be a tiny bit faster since we're just comparing pointers instead of calling nir_src_equal. Reviewed-by: Timothy Arceri Cc: "13.0" --- src/compiler/nir/nir_search.c | 16 +++++++++++----- 1 file changed, 11 insertions(+), 5 deletions(-) diff --git a/src/compiler/nir/nir_search.c b/src/compiler/nir/nir_search.c index b34b13fdb89..10a0941fa20 100644 --- a/src/compiler/nir/nir_search.c +++ b/src/compiler/nir/nir_search.c @@ -98,6 +98,16 @@ match_value(const nir_search_value *value, nir_alu_instr *instr, unsigned src, { uint8_t new_swizzle[4]; + /* Searching only works on SSA values because, if it's not SSA, we can't + * know if the value changed between one instance of that value in the + * expression and another. Also, the replace operation will place reads of + * that value right before the last instruction in the expression we're + * replacing so those reads will happen after the original reads and may + * not be valid if they're register reads. + */ + if (!instr->src[src].src.is_ssa) + return false; + /* If the source is an explicitly sized source, then we need to reset * both the number of components and the swizzle. */ @@ -116,9 +126,6 @@ match_value(const nir_search_value *value, nir_alu_instr *instr, unsigned src, switch (value->type) { case nir_search_value_expression: - if (!instr->src[src].src.is_ssa) - return false; - if (instr->src[src].src.ssa->parent_instr->type != nir_instr_type_alu) return false; @@ -131,8 +138,7 @@ match_value(const nir_search_value *value, nir_alu_instr *instr, unsigned src, assert(var->variable < NIR_SEARCH_MAX_VARIABLES); if (state->variables_seen & (1 << var->variable)) { - if (!nir_srcs_equal(state->variables[var->variable].src, - instr->src[src].src)) + if (state->variables[var->variable].src.ssa != instr->src[src].src.ssa) return false; assert(!instr->src[src].abs && !instr->src[src].negate); -- 2.30.2