As noticed we are looking for INDIRECT_REF with allows_mem to avoid a copy since then we're sure the operand is in memory (assuming *& is folded). But INDIRECT_REFs are no longer a thing, the following replaces the check with a check for a MEM_REF with a non-ADDR_EXPR operand. This should fix the regression part without fully exploring all possibilities around tcc_reference operands.
I've placed an assert that we do not see an INDIRECT_REF here. While we gimplify asm operands we never do any checking on its IL afterwards. Bootstrapped on x86_64-unknown-linux-gnu, testing in progress. OK if that succeeds? Thanks, Richard. 2022-03-09 Richard Biener <rguent...@suse.de> * cfgexpand.c (expand_gimple_asm): Special-case MEM_REF with non-decl operand, avoiding a copy. --- gcc/cfgexpand.cc | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/gcc/cfgexpand.cc b/gcc/cfgexpand.cc index 4f99f040450..d3cc77d2ca9 100644 --- a/gcc/cfgexpand.cc +++ b/gcc/cfgexpand.cc @@ -3290,7 +3290,10 @@ expand_asm_stmt (gasm *stmt) generating_concat_p = 0; - if ((TREE_CODE (val) == INDIRECT_REF && allows_mem) + gcc_assert (TREE_CODE (val) != INDIRECT_REF); + if (((TREE_CODE (val) == MEM_REF + && TREE_CODE (TREE_OPERAND (val, 0)) != ADDR_EXPR) + && allows_mem) || (DECL_P (val) && (allows_mem || REG_P (DECL_RTL (val))) && ! (REG_P (DECL_RTL (val)) -- 2.34.1