This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.

Index Nav:	[Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav:	[Date Prev] [Date Next]	[Thread Prev] [Thread Next]
Other format:	[Raw text]

[RFC][PR61839]Convert CST BINOP COND_EXPR to COND_EXPR ? (CST BINOP 1) : (CST BINOP 0)

From: kugan <kugan dot vivekanandarajah at linaro dot org>
To: "gcc-patches at gcc dot gnu dot org" <gcc-patches at gcc dot gnu dot org>, Richard Biener <richard dot guenther at gmail dot com>
Date: Sun, 17 Apr 2016 09:14:01 +1000
Subject: [RFC][PR61839]Convert CST BINOP COND_EXPR to COND_EXPR ? (CST BINOP 1) : (CST BINOP 0)
Authentication-results: sourceware.org; auth=none

As explained in PR61839,

Following difference results in extra instructions:
-  c = b != 0 ? 486097858 : 972195717;
+  c = a + 972195718 >> (b != 0);

As suggested in PR, attached patch converts CST BINOP COND_EXPR toCOND_EXPR ? (CST BINOP 1) : (CST BINOP 0).

Bootstrapped and regression tested for x86-64-linux-gnu with no newregression. Is this OK for statege-1.


Thanks,
Kugan

gcc/ChangeLog:

2016-04-17  Kugan Vivekanandarajah  <kuganv@linaro.org>

	* tree-vrp.c (simplify_stmt_using_ranges): Convert CST BINOP COND_EXPR to
	COND_EXPR ? (CST BINOP 1) : (CST BINOP 0) when possible.

Attachment: pr61839.txt
Description: Text document

Follow-Ups:
- Re: [RFC][PR61839]Convert CST BINOP COND_EXPR to COND_EXPR ? (CST BINOP 1) : (CST BINOP 0)
  - From: Richard Biener

Index Nav:	[Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav:	[Date Prev] [Date Next]	[Thread Prev] [Thread Next]