runtime: don't use linkname to refer to internal/cpu

The runtime package already imports the internal/cpu package, so there
is no reason for it to use go:linkname comments to refer to
internal/cpu functions and variables. Since internal/cpu is internal,
we can just export those names. Removing the obscurity of go:linkname
outweighs the minor additional complexity added to the internal/cpu API.

Change-Id: Id89951b7f3fc67cd9bce67ac6d01d44a647a10ad
Reviewed-on: https://go-review.googlesource.com/128755
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Martin Möhrmann <moehrmann@google.com>

4 files changed, 50 insertions, 50 deletions

diff --git a/src/internal/cpu/cpu.go b/src/internal/cpu/cpu.go
index 701584dd3d..f2dfadbff8 100644
--- a/src/internal/cpu/cpu.go
+++ b/src/internal/cpu/cpu.go
@@ -6,9 +6,10 @@
 // used by the Go standard library.
 package cpu
 
-// debugOptions is set to true by the runtime if go was compiled with GOEXPERIMENT=debugcpu
-// and GOOS is Linux or Darwin. This variable is linknamed in runtime/proc.go.
-var debugOptions bool
+// DebugOptions is set to true by the runtime if go was compiled with GOEXPERIMENT=debugcpu
+// and GOOS is Linux or Darwin.
+// This should not be changed after it is initialized.
+var DebugOptions bool
 
 // CacheLinePad is used to pad structs to avoid false sharing.
 type CacheLinePad struct{ _ [CacheLineSize]byte }
@@ -121,11 +122,11 @@ type s390x struct {
 	_               CacheLinePad
 }
 
-// initialize examines the processor and sets the relevant variables above.
+// Initialize examines the processor and sets the relevant variables above.
 // This is called by the runtime package early in program initialization,
 // before normal init functions are run. env is set by runtime on Linux and Darwin
 // if go was compiled with GOEXPERIMENT=debugcpu.
-func initialize(env string) {
+func Initialize(env string) {
 	doinit()
 	processOptions(env)
 }
diff --git a/src/internal/cpu/cpu_arm64.go b/src/internal/cpu/cpu_arm64.go
index 48607575ba..77b617e49f 100644
--- a/src/internal/cpu/cpu_arm64.go
+++ b/src/internal/cpu/cpu_arm64.go
@@ -7,10 +7,10 @@ package cpu
 const CacheLineSize = 64
 
 // arm64 doesn't have a 'cpuid' equivalent, so we rely on HWCAP/HWCAP2.
-// These are linknamed in runtime/os_linux_arm64.go and are initialized by
-// archauxv().
-var hwcap uint
-var hwcap2 uint
+// These are initialized by archauxv in runtime/os_linux_arm64.go.
+// These should not be changed after they are initialized.
+var HWCap uint
+var HWCap2 uint
 
 // HWCAP/HWCAP2 bits. These are exposed by Linux.
 const (
@@ -71,30 +71,30 @@ func doinit() {
 	}
 
 	// HWCAP feature bits
-	ARM64.HasFP = isSet(hwcap, hwcap_FP)
-	ARM64.HasASIMD = isSet(hwcap, hwcap_ASIMD)
-	ARM64.HasEVTSTRM = isSet(hwcap, hwcap_EVTSTRM)
-	ARM64.HasAES = isSet(hwcap, hwcap_AES)
-	ARM64.HasPMULL = isSet(hwcap, hwcap_PMULL)
-	ARM64.HasSHA1 = isSet(hwcap, hwcap_SHA1)
-	ARM64.HasSHA2 = isSet(hwcap, hwcap_SHA2)
-	ARM64.HasCRC32 = isSet(hwcap, hwcap_CRC32)
-	ARM64.HasATOMICS = isSet(hwcap, hwcap_ATOMICS)
-	ARM64.HasFPHP = isSet(hwcap, hwcap_FPHP)
-	ARM64.HasASIMDHP = isSet(hwcap, hwcap_ASIMDHP)
-	ARM64.HasCPUID = isSet(hwcap, hwcap_CPUID)
-	ARM64.HasASIMDRDM = isSet(hwcap, hwcap_ASIMDRDM)
-	ARM64.HasJSCVT = isSet(hwcap, hwcap_JSCVT)
-	ARM64.HasFCMA = isSet(hwcap, hwcap_FCMA)
-	ARM64.HasLRCPC = isSet(hwcap, hwcap_LRCPC)
-	ARM64.HasDCPOP = isSet(hwcap, hwcap_DCPOP)
-	ARM64.HasSHA3 = isSet(hwcap, hwcap_SHA3)
-	ARM64.HasSM3 = isSet(hwcap, hwcap_SM3)
-	ARM64.HasSM4 = isSet(hwcap, hwcap_SM4)
-	ARM64.HasASIMDDP = isSet(hwcap, hwcap_ASIMDDP)
-	ARM64.HasSHA512 = isSet(hwcap, hwcap_SHA512)
-	ARM64.HasSVE = isSet(hwcap, hwcap_SVE)
-	ARM64.HasASIMDFHM = isSet(hwcap, hwcap_ASIMDFHM)
+	ARM64.HasFP = isSet(HWCap, hwcap_FP)
+	ARM64.HasASIMD = isSet(HWCap, hwcap_ASIMD)
+	ARM64.HasEVTSTRM = isSet(HWCap, hwcap_EVTSTRM)
+	ARM64.HasAES = isSet(HWCap, hwcap_AES)
+	ARM64.HasPMULL = isSet(HWCap, hwcap_PMULL)
+	ARM64.HasSHA1 = isSet(HWCap, hwcap_SHA1)
+	ARM64.HasSHA2 = isSet(HWCap, hwcap_SHA2)
+	ARM64.HasCRC32 = isSet(HWCap, hwcap_CRC32)
+	ARM64.HasATOMICS = isSet(HWCap, hwcap_ATOMICS)
+	ARM64.HasFPHP = isSet(HWCap, hwcap_FPHP)
+	ARM64.HasASIMDHP = isSet(HWCap, hwcap_ASIMDHP)
+	ARM64.HasCPUID = isSet(HWCap, hwcap_CPUID)
+	ARM64.HasASIMDRDM = isSet(HWCap, hwcap_ASIMDRDM)
+	ARM64.HasJSCVT = isSet(HWCap, hwcap_JSCVT)
+	ARM64.HasFCMA = isSet(HWCap, hwcap_FCMA)
+	ARM64.HasLRCPC = isSet(HWCap, hwcap_LRCPC)
+	ARM64.HasDCPOP = isSet(HWCap, hwcap_DCPOP)
+	ARM64.HasSHA3 = isSet(HWCap, hwcap_SHA3)
+	ARM64.HasSM3 = isSet(HWCap, hwcap_SM3)
+	ARM64.HasSM4 = isSet(HWCap, hwcap_SM4)
+	ARM64.HasASIMDDP = isSet(HWCap, hwcap_ASIMDDP)
+	ARM64.HasSHA512 = isSet(HWCap, hwcap_SHA512)
+	ARM64.HasSVE = isSet(HWCap, hwcap_SVE)
+	ARM64.HasASIMDFHM = isSet(HWCap, hwcap_ASIMDFHM)
 }
 
 func isSet(hwc uint, value uint) bool {
diff --git a/src/internal/cpu/cpu_ppc64x.go b/src/internal/cpu/cpu_ppc64x.go
index 995cf02081..d3f02efa7f 100644
--- a/src/internal/cpu/cpu_ppc64x.go
+++ b/src/internal/cpu/cpu_ppc64x.go
@@ -9,10 +9,10 @@ package cpu
 const CacheLineSize = 128
 
 // ppc64x doesn't have a 'cpuid' equivalent, so we rely on HWCAP/HWCAP2.
-// These are linknamed in runtime/os_linux_ppc64x.go and are initialized by
-// archauxv().
-var hwcap uint
-var hwcap2 uint
+// These are initialized by archauxv in runtime/os_linux_ppc64x.go.
+// These should not be changed after they are initialized.
+var HWCap uint
+var HWCap2 uint
 
 // HWCAP/HWCAP2 bits. These are exposed by the kernel.
 const (
@@ -48,19 +48,19 @@ func doinit() {
 	}
 
 	// HWCAP feature bits
-	PPC64.HasVMX = isSet(hwcap, _PPC_FEATURE_HAS_ALTIVEC)
-	PPC64.HasDFP = isSet(hwcap, _PPC_FEATURE_HAS_DFP)
-	PPC64.HasVSX = isSet(hwcap, _PPC_FEATURE_HAS_VSX)
+	PPC64.HasVMX = isSet(HWCap, _PPC_FEATURE_HAS_ALTIVEC)
+	PPC64.HasDFP = isSet(HWCap, _PPC_FEATURE_HAS_DFP)
+	PPC64.HasVSX = isSet(HWCap, _PPC_FEATURE_HAS_VSX)
 
 	// HWCAP2 feature bits
-	PPC64.IsPOWER8 = isSet(hwcap2, _PPC_FEATURE2_ARCH_2_07)
-	PPC64.HasHTM = isSet(hwcap2, _PPC_FEATURE2_HAS_HTM)
-	PPC64.HasISEL = isSet(hwcap2, _PPC_FEATURE2_HAS_ISEL)
-	PPC64.HasVCRYPTO = isSet(hwcap2, _PPC_FEATURE2_HAS_VEC_CRYPTO)
-	PPC64.HasHTMNOSC = isSet(hwcap2, _PPC_FEATURE2_HTM_NOSC)
-	PPC64.IsPOWER9 = isSet(hwcap2, _PPC_FEATURE2_ARCH_3_00)
-	PPC64.HasDARN = isSet(hwcap2, _PPC_FEATURE2_DARN)
-	PPC64.HasSCV = isSet(hwcap2, _PPC_FEATURE2_SCV)
+	PPC64.IsPOWER8 = isSet(HWCap2, _PPC_FEATURE2_ARCH_2_07)
+	PPC64.HasHTM = isSet(HWCap2, _PPC_FEATURE2_HAS_HTM)
+	PPC64.HasISEL = isSet(HWCap2, _PPC_FEATURE2_HAS_ISEL)
+	PPC64.HasVCRYPTO = isSet(HWCap2, _PPC_FEATURE2_HAS_VEC_CRYPTO)
+	PPC64.HasHTMNOSC = isSet(HWCap2, _PPC_FEATURE2_HTM_NOSC)
+	PPC64.IsPOWER9 = isSet(HWCap2, _PPC_FEATURE2_ARCH_3_00)
+	PPC64.HasDARN = isSet(HWCap2, _PPC_FEATURE2_DARN)
+	PPC64.HasSCV = isSet(HWCap2, _PPC_FEATURE2_SCV)
 }
 
 func isSet(hwc uint, value uint) bool {
diff --git a/src/internal/cpu/export_test.go b/src/internal/cpu/export_test.go
index 4e53c5a084..91bfc1bbc3 100644
--- a/src/internal/cpu/export_test.go
+++ b/src/internal/cpu/export_test.go
@@ -5,6 +5,5 @@
 package cpu
 
 var (
-	Options      = options
-	DebugOptions = debugOptions
+	Options = options
 )