From 0091315ad7f2c278f3d4e7cc4453fec5bed43869 Mon Sep 17 00:00:00 2001 From: Michael Munday Date: Thu, 28 Feb 2019 04:00:03 -0500 Subject: [PATCH] poly1305: use x/sys/cpu for s390x feature detection Use the recently added CPU feature detection API rather than custom assembly. This will need to be updated to use 'internal/cpu' when the package is revendored into std. Change-Id: Ia99c51c7409fe4fabcd88fdf5ff19772c1ca2257 Reviewed-on: https://go-review.googlesource.com/c/164382 Reviewed-by: Brad Fitzpatrick Run-TryBot: Brad Fitzpatrick TryBot-Result: Gobot Gobot --- poly1305/sum_s390x.go | 17 +++++------------ poly1305/sum_s390x.s | 22 ---------------------- poly1305/sum_vmsl_s390x.s | 22 ---------------------- 3 files changed, 5 insertions(+), 56 deletions(-) diff --git a/poly1305/sum_s390x.go b/poly1305/sum_s390x.go index 7a266ce..ec99e07 100644 --- a/poly1305/sum_s390x.go +++ b/poly1305/sum_s390x.go @@ -6,16 +6,9 @@ package poly1305 -// hasVectorFacility reports whether the machine supports -// the vector facility (vx). -func hasVectorFacility() bool - -// hasVMSLFacility reports whether the machine supports -// Vector Multiply Sum Logical (VMSL). -func hasVMSLFacility() bool - -var hasVX = hasVectorFacility() -var hasVMSL = hasVMSLFacility() +import ( + "golang.org/x/sys/cpu" +) // poly1305vx is an assembly implementation of Poly1305 that uses vector // instructions. It must only be called if the vector facility (vx) is @@ -33,12 +26,12 @@ func poly1305vmsl(out *[16]byte, m *byte, mlen uint64, key *[32]byte) // 16-byte result into out. Authenticating two different messages with the same // key allows an attacker to forge messages at will. func Sum(out *[16]byte, m []byte, key *[32]byte) { - if hasVX { + if cpu.S390X.HasVX { var mPtr *byte if len(m) > 0 { mPtr = &m[0] } - if hasVMSL && len(m) > 256 { + if cpu.S390X.HasVXE && len(m) > 256 { poly1305vmsl(out, mPtr, uint64(len(m)), key) } else { poly1305vx(out, mPtr, uint64(len(m)), key) diff --git a/poly1305/sum_s390x.s b/poly1305/sum_s390x.s index 356c07a..ca5a309 100644 --- a/poly1305/sum_s390x.s +++ b/poly1305/sum_s390x.s @@ -376,25 +376,3 @@ b1: MOVD $0, R3 BR multiply - -TEXT ·hasVectorFacility(SB), NOSPLIT, $24-1 - MOVD $x-24(SP), R1 - XC $24, 0(R1), 0(R1) // clear the storage - MOVD $2, R0 // R0 is the number of double words stored -1 - WORD $0xB2B01000 // STFLE 0(R1) - XOR R0, R0 // reset the value of R0 - MOVBZ z-8(SP), R1 - AND $0x40, R1 - BEQ novector - -vectorinstalled: - // check if the vector instruction has been enabled - VLEIB $0, $0xF, V16 - VLGVB $0, V16, R1 - CMPBNE R1, $0xF, novector - MOVB $1, ret+0(FP) // have vx - RET - -novector: - MOVB $0, ret+0(FP) // no vx - RET diff --git a/poly1305/sum_vmsl_s390x.s b/poly1305/sum_vmsl_s390x.s index e548020..e60bbc1 100644 --- a/poly1305/sum_vmsl_s390x.s +++ b/poly1305/sum_vmsl_s390x.s @@ -907,25 +907,3 @@ square: MULTIPLY(H0_0, H1_0, H2_0, H0_1, H1_1, H2_1, R_0, R_1, R_2, R5_1, R5_2, M0, M1, M2, M3, M4, M5, T_0, T_1, T_2, T_3, T_4, T_5, T_6, T_7, T_8, T_9) REDUCE2(H0_0, H1_0, H2_0, M0, M1, M2, M3, M4, T_9, T_10, H0_1, M5) BR next - -TEXT ·hasVMSLFacility(SB), NOSPLIT, $24-1 - MOVD $x-24(SP), R1 - XC $24, 0(R1), 0(R1) // clear the storage - MOVD $2, R0 // R0 is the number of double words stored -1 - WORD $0xB2B01000 // STFLE 0(R1) - XOR R0, R0 // reset the value of R0 - MOVBZ z-8(SP), R1 - AND $0x01, R1 - BEQ novmsl - -vectorinstalled: - // check if the vector instruction has been enabled - VLEIB $0, $0xF, V16 - VLGVB $0, V16, R1 - CMPBNE R1, $0xF, novmsl - MOVB $1, ret+0(FP) // have vx - RET - -novmsl: - MOVB $0, ret+0(FP) // no vx - RET