From mboxrd@z Thu Jan 1 00:00:00 1970 From: Luc Van Oostenryck Subject: [PATCH v3 17/30] llvm: fix output_op_store() which modify its operand Date: Sun, 19 Mar 2017 02:42:14 +0100 Message-ID: <20170319014227.8833-18-luc.vanoostenryck@gmail.com> References: <20170319014227.8833-1-luc.vanoostenryck@gmail.com> Return-path: Received: from mail-wr0-f195.google.com ([209.85.128.195]:35304 "EHLO mail-wr0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751398AbdCSBm4 (ORCPT ); Sat, 18 Mar 2017 21:42:56 -0400 Received: by mail-wr0-f195.google.com with SMTP id u108so13841309wrb.2 for ; Sat, 18 Mar 2017 18:42:55 -0700 (PDT) In-Reply-To: <20170319014227.8833-1-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: Christopher Li , 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 94ebc9577..e01406281 100644 --- a/sparse-llvm.c +++ b/sparse-llvm.c @@ -651,16 +651,14 @@ 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. + */ -- 2.12.0