From 0f63602c76d7abe750efa402b2648100da360adb Mon Sep 17 00:00:00 2001 From: Matthew Wahab Date: Mon, 1 Jun 2015 15:21:02 +0000 Subject: PR target/65697 * config/aarch64/aarch64.c (aarch64_split_compare_and_swap): Check for __sync memory models, emit initial loads and final barriers as appropriate. git-svn-id: https://gcc.gnu.org/svn/gcc/trunk@223984 138bc75d-0d04-0410-961f-82ee72b054a4 --- gcc/ChangeLog | 7 +++++++ gcc/config/aarch64/aarch64.c | 18 ++++++++++++++++-- 2 files changed, 23 insertions(+), 2 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 0c109c33c0a..b0c172c6f15 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,10 @@ +2015-06-01 Matthew Wahab + + PR target/65697 + * config/aarch64/aarch64.c (aarch64_split_compare_and_swap): Check + for __sync memory models, emit initial loads and final barriers as + appropriate. + 2015-06-01 Matthew Wahab PR target/65697 diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c index 93bea074d68..62c8c8fe47a 100644 --- a/gcc/config/aarch64/aarch64.c +++ b/gcc/config/aarch64/aarch64.c @@ -9436,14 +9436,18 @@ aarch64_split_compare_and_swap (rtx operands[]) bool is_weak; rtx_code_label *label1, *label2; rtx x, cond; + enum memmodel model; + rtx model_rtx; rval = operands[0]; mem = operands[1]; oldval = operands[2]; newval = operands[3]; is_weak = (operands[4] != const0_rtx); + model_rtx = operands[5]; scratch = operands[7]; mode = GET_MODE (mem); + model = memmodel_from_int (INTVAL (model_rtx)); label1 = NULL; if (!is_weak) @@ -9453,7 +9457,13 @@ aarch64_split_compare_and_swap (rtx operands[]) } label2 = gen_label_rtx (); - aarch64_emit_load_exclusive (mode, rval, mem, operands[5]); + /* The initial load can be relaxed for a __sync operation since a final + barrier will be emitted to stop code hoisting. */ + if (is_mm_sync (model)) + aarch64_emit_load_exclusive (mode, rval, mem, + GEN_INT (MEMMODEL_RELAXED)); + else + aarch64_emit_load_exclusive (mode, rval, mem, model_rtx); cond = aarch64_gen_compare_reg (NE, rval, oldval); x = gen_rtx_NE (VOIDmode, cond, const0_rtx); @@ -9461,7 +9471,7 @@ aarch64_split_compare_and_swap (rtx operands[]) gen_rtx_LABEL_REF (Pmode, label2), pc_rtx); aarch64_emit_unlikely_jump (gen_rtx_SET (pc_rtx, x)); - aarch64_emit_store_exclusive (mode, scratch, mem, newval, operands[5]); + aarch64_emit_store_exclusive (mode, scratch, mem, newval, model_rtx); if (!is_weak) { @@ -9478,6 +9488,10 @@ aarch64_split_compare_and_swap (rtx operands[]) } emit_label (label2); + + /* Emit any final barrier needed for a __sync operation. */ + if (is_mm_sync (model)) + aarch64_emit_post_barrier (model); } /* Split an atomic operation. */ -- cgit v1.2.3