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Re: more tidying of x86 feature tests

From: Uros Bizjak <ubizjak at gmail dot com>
To: GCC Patches <gcc-patches at gcc dot gnu dot org>
Cc: Richard Henderson <rth at redhat dot com>, Jan Hubicka <jh at suse dot cz>
Date: Tue, 06 Mar 2007 19:35:27 +0100
Subject: Re: more tidying of x86 feature tests

Richard Henderson wrote:

+  /* ??? Any idea why this is unconditionally disabled for 64-bit?  */
+  if (TARGET_64BIT)
+    TARGET_USE_SAHF = 0;

IIRC, early x86_64 ISA draft didn't have SAHF and some prototypes didn't handle this insn.

At least for AMD, there is no need to disable this, as sahf is DirectPath latency 1 insn.

Uros.

Follow-Ups:
- Re: more tidying of x86 feature tests
  - From: Jan Hubicka

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