From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luc Van Oostenryck Subject: [PATCH 03/13] llvm: fix output_op_store() which modify its operand Date: Sun, 5 Mar 2017 12:20:37 +0100 Message-ID: <20170305112047.3411-4-luc.vanoostenryck@gmail.com> References: <20170305112047.3411-1-luc.vanoostenryck@gmail.com> Return-path: Received: from mail-wm0-f65.google.com ([74.125.82.65]:33179 "EHLO mail-wm0-f65.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752470AbdCELai (ORCPT ); Sun, 5 Mar 2017 06:30:38 -0500 Received: by mail-wm0-f65.google.com with SMTP id n11so9502920wma.0 for ; Sun, 05 Mar 2017 03:30:36 -0800 (PST) In-Reply-To: <20170305112047.3411-1-luc.vanoostenryck@gmail.com> Sender: linux-sparse-owner@vger.kernel.org List-Id: linux-sparse@vger.kernel.org To: linux-sparse@vger.kernel.org Cc: Dibyendu Majumdar , Luc Van Oostenryck In sparse-llvm the field 'priv' of a pseudo is used to store the corresponding LLVMValueRef. This field is normaly assigned when processing the instruction that produces the speudo. In output_op_store(), the field insn->target->priv is overwritten by the LLVMValueRef returned by LLVMBuildStore(). It's unclear what this return value is: - this corrupts the pseudo, making it unusable in subsequent instructions. - there is no reason to change this field anyway. Fix this by removing the assignment to insn->target->priv in output_op_store(). Reported-by: Dibyendu Majumdar Signed-off-by: Luc Van Oostenryck --- sparse-llvm.c | 6 ++---- validation/backend/store-x2.c | 16 ++++++++++++++++ 2 files changed, 18 insertions(+), 4 deletions(-) create mode 100644 validation/backend/store-x2.c diff --git a/sparse-llvm.c b/sparse-llvm.c index d48b3b20a..665b6c7dc 100644 --- a/sparse-llvm.c +++ b/sparse-llvm.c @@ -646,16 +646,14 @@ static void output_op_load(struct function *fn, struct instruction *insn) static void output_op_store(struct function *fn, struct instruction *insn) { - LLVMValueRef addr, target, target_in; + LLVMValueRef addr, target_in; addr = calc_memop_addr(fn, insn); target_in = pseudo_to_value(fn, insn, insn->target); /* perform store */ - target = LLVMBuildStore(fn->builder, target_in, addr); - - insn->target->priv = target; + LLVMBuildStore(fn->builder, target_in, addr); } static LLVMValueRef bool_value(struct function *fn, LLVMValueRef value) diff --git a/validation/backend/store-x2.c b/validation/backend/store-x2.c new file mode 100644 index 000000000..5ccc9b43a --- /dev/null +++ b/validation/backend/store-x2.c @@ -0,0 +1,16 @@ +void foo(int *p, int a, int b); +void foo(int *p, int a, int b) +{ + int c = a + b; + + p[0] = c; + p[1] = c; +} + +/* + * check-name: store-x2 + * check-command: sparsec -c $file -o tmp.o + * check-description: Verify in output_op_store() that + * the first store doesn't mess anymore with the + * 'target' and thus making the second store unusable. + */ -- 2.11.1