From 564cf83d79d6199de7ea9eb047aa3a244d9bb52e Mon Sep 17 00:00:00 2001 From: Richard Sandiford Date: Mon, 8 May 2017 16:18:49 +0000 Subject: [PATCH] [AArch64] Tighten move constraints for symbolic operands The movsi and movdi constraints allowed the source to be any absolute symbolic expression ("S"). That's OK for operands that have already been vetted by the aarch64_mov_operand predicate but causes problems if the register allocator substitutes an equivalence (the usual "the constraints can't accept more than the predicates" restriction). Although all other uses of "S" in the backend are redundant and could in principle be removed, "S" itself is a publicly-documented constraint and so we'd have to keep its definition. This patch therefore adds a new "Usa" constraint for legitimate absolute address operands. 2017-05-08 Richard Sandiford gcc/ * config/aarch64/constraints.md (Usa): New constraint. * config/aarch64/aarch64.md (*movsi_aarch64, *movdi_aarch64): Use it. From-SVN: r247746 --- gcc/ChangeLog | 5 +++++ gcc/config/aarch64/aarch64.md | 4 ++-- gcc/config/aarch64/constraints.md | 8 ++++++++ 3 files changed, 15 insertions(+), 2 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index fdc15111052..58693c5a476 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2017-05-08 Richard Sandiford + + * config/aarch64/constraints.md (Usa): New constraint. + * config/aarch64/aarch64.md (*movsi_aarch64, *movdi_aarch64): Use it. + 2017-05-08 Thomas Preud'homme * config.gcc (arm*-*-*): Set TM_MULTILIB_CONFIG from diff --git a/gcc/config/aarch64/aarch64.md b/gcc/config/aarch64/aarch64.md index c522e87ebde..7cc32dd037c 100644 --- a/gcc/config/aarch64/aarch64.md +++ b/gcc/config/aarch64/aarch64.md @@ -1031,7 +1031,7 @@ (define_insn_and_split "*movsi_aarch64" [(set (match_operand:SI 0 "nonimmediate_operand" "=r,k,r,r,r,r,*w,m, m,r,r ,*w,r,*w") - (match_operand:SI 1 "aarch64_mov_operand" " r,r,k,M,n,m, m,rZ,*w,S,Ush,rZ,w,*w"))] + (match_operand:SI 1 "aarch64_mov_operand" " r,r,k,M,n,m, m,rZ,*w,Usa,Ush,rZ,w,*w"))] "(register_operand (operands[0], SImode) || aarch64_reg_or_zero (operands[1], SImode))" "@ @@ -1063,7 +1063,7 @@ (define_insn_and_split "*movdi_aarch64" [(set (match_operand:DI 0 "nonimmediate_operand" "=r,k,r,r,r,r,*w,m, m,r,r, *w,r,*w,w") - (match_operand:DI 1 "aarch64_mov_operand" " r,r,k,N,n,m, m,rZ,*w,S,Ush,rZ,w,*w,Dd"))] + (match_operand:DI 1 "aarch64_mov_operand" " r,r,k,N,n,m, m,rZ,*w,Usa,Ush,rZ,w,*w,Dd"))] "(register_operand (operands[0], DImode) || aarch64_reg_or_zero (operands[1], DImode))" "@ diff --git a/gcc/config/aarch64/constraints.md b/gcc/config/aarch64/constraints.md index b8293376fde..b43f08b7bbd 100644 --- a/gcc/config/aarch64/constraints.md +++ b/gcc/config/aarch64/constraints.md @@ -98,6 +98,14 @@ (and (match_code "high") (match_test "aarch64_valid_symref (XEXP (op, 0), GET_MODE (XEXP (op, 0)))"))) +(define_constraint "Usa" + "@internal + A constraint that matches an absolute symbolic address that can be + loaded by a single ADR." + (and (match_code "const,symbol_ref,label_ref") + (match_test "aarch64_symbolic_address_p (op)") + (match_test "aarch64_mov_operand_p (op, GET_MODE (op))"))) + (define_constraint "Uss" "@internal A constraint that matches an immediate shift constant in SImode." -- 2.30.2