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helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -26 X-Spam_score: -2.7 X-Spam_bar: -- X-Spam_report: (-2.7 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.649, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H5=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org No difference in generated code, but the XOR-based formula is easily understood on its own. This will make more sense once ADD/SUB stop using dst^src1^src2 to compute AF. Signed-off-by: Paolo Bonzini --- target/i386/tcg/cc_helper_template.h.inc | 10 ++-------- 1 file changed, 2 insertions(+), 8 deletions(-) diff --git a/target/i386/tcg/cc_helper_template.h.inc b/target/i386/tcg/cc_helper_template.h.inc index 9aff16b8801..b821e5bca3b 100644 --- a/target/i386/tcg/cc_helper_template.h.inc +++ b/target/i386/tcg/cc_helper_template.h.inc @@ -175,13 +175,10 @@ static uint32_t glue(compute_all_logic, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1) static uint32_t glue(compute_all_inc, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1) { uint32_t cf, pf, af, zf, sf, of; - DATA_TYPE src2; cf = src1; - src1 = dst - 1; - src2 = 1; pf = compute_pf(dst); - af = (dst ^ src1 ^ src2) & CC_A; + af = (dst ^ (dst - 1)) & CC_A; /* bits 0..3 are all clear */ zf = (dst == 0) * CC_Z; sf = lshift(dst, 8 - DATA_BITS) & CC_S; of = (dst == SIGN_MASK) * CC_O; @@ -191,13 +188,10 @@ static uint32_t glue(compute_all_inc, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1) static uint32_t glue(compute_all_dec, SUFFIX)(DATA_TYPE dst, DATA_TYPE src1) { uint32_t cf, pf, af, zf, sf, of; - DATA_TYPE src2; cf = src1; - src1 = dst + 1; - src2 = 1; pf = compute_pf(dst); - af = (dst ^ src1 ^ src2) & CC_A; + af = (dst ^ (dst + 1)) & CC_A; /* bits 0..3 are all set */ zf = (dst == 0) * CC_Z; sf = lshift(dst, 8 - DATA_BITS) & CC_S; of = (dst == SIGN_MASK - 1) * CC_O;