math: simplify hasVX checking on s390x

Originally, we use an assembly function that returns a boolean result to
tell whether the machine has vector facility or not. It is now no longer
needed when we can directly use cpu.S390X.HasVX variable.

Change-Id: Ic3ffeb9e63238ef41406d97cdc42502145ddb454
Reviewed-on: https://go-review.googlesource.com/c/go/+/230319
Reviewed-by: Michael Munday <mike.munday@ibm.com>
Run-TryBot: Michael Munday <mike.munday@ibm.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

diff --git a/src/math/arith_s390x.go b/src/math/arith_s390x.go
index 4a1d2f8e5c4ec1d5017e285ce1ff64df8203b826..90a7d4f710ef7c72d2e23b5545ab4d699b84f4f5 100644 (file)
--- a/src/math/arith_s390x.go
+++ b/src/math/arith_s390x.go
@@ -4,6 +4,8 @@
 
 package math
 
+import "internal/cpu"
+
 func log10TrampolineSetup(x float64) float64
 func log10Asm(x float64) float64
 
@@ -70,8 +72,6 @@ func expm1Asm(x float64) float64
 func powTrampolineSetup(x, y float64) float64
 func powAsm(x, y float64) float64
 
-// hasVectorFacility reports whether the machine has the z/Architecture
+// hasVX reports whether the machine has the z/Architecture
 // vector facility installed and enabled.
-func hasVectorFacility() bool
-
-var hasVX = hasVectorFacility()
+var hasVX = cpu.S390X.HasVX

diff --git a/src/math/stubs_s390x.s b/src/math/stubs_s390x.s
index 021bc1fa8f3ff50f3462216a9bbcedc1c56adefe..d0087aba15a6ce30d8fb4dc15434a13a0c686181 100644 (file)
--- a/src/math/stubs_s390x.s
+++ b/src/math/stubs_s390x.s
@@ -28,29 +28,6 @@ TEXT ·Mod(SB), NOSPLIT, $0
 TEXT ·Remainder(SB), NOSPLIT, $0
        BR ·remainder(SB)
 
-// if go assembly use vector instruction
-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
-
 TEXT ·Log10(SB), NOSPLIT, $0
        MOVD ·log10vectorfacility+0x00(SB), R1
        BR   (R1)