From 3adb57d3e689f0c3da7a26df52e9218afb18d94f Mon Sep 17 00:00:00 2001
From: Meng Zhuo <mengzhuo1203@gmail.com>
Date: Thu, 12 Sep 2024 20:15:56 +0800
Subject: [PATCH] all: implement plugin build mode for riscv64
Change-Id: I8d7bbeebbf4a46f2fd8d630b1edbaf79b8ffccc5
Reviewed-on: https://go-review.googlesource.com/c/go/+/420114
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Joel Sing <joel@sing.id.au>
TryBot-Bypass: Joel Sing <joel@sing.id.au>
---
src/cmd/dist/test.go | 2 +-
src/cmd/internal/obj/riscv/obj.go | 121 +++++++++++++++++++++++++++
src/cmd/link/internal/riscv64/asm.go | 21 ++++-
src/internal/platform/supported.go | 2 +-
src/runtime/asm_riscv64.s | 9 ++
5 files changed, 152 insertions(+), 3 deletions(-)
diff --git a/src/cmd/dist/test.go b/src/cmd/dist/test.go
index 0ffcabe416..b1e3929113 100644
--- a/src/cmd/dist/test.go
+++ b/src/cmd/dist/test.go
@@ -1659,7 +1659,7 @@ func buildModeSupported(compiler, buildmode, goos, goarch string) bool {
case "plugin":
switch platform {
- case "linux/amd64", "linux/arm", "linux/arm64", "linux/386", "linux/loong64", "linux/s390x", "linux/ppc64le",
+ case "linux/amd64", "linux/arm", "linux/arm64", "linux/386", "linux/loong64", "linux/riscv64", "linux/s390x", "linux/ppc64le",
"android/amd64", "android/386",
"darwin/amd64", "darwin/arm64",
"freebsd/amd64":
diff --git a/src/cmd/internal/obj/riscv/obj.go b/src/cmd/internal/obj/riscv/obj.go
index 2055f4836e..44a2246e1f 100644
--- a/src/cmd/internal/obj/riscv/obj.go
+++ b/src/cmd/internal/obj/riscv/obj.go
@@ -177,6 +177,127 @@ func progedit(ctxt *obj.Link, p *obj.Prog, newprog obj.ProgAlloc) {
p.From.Offset = 0
}
}
+
+ if ctxt.Flag_dynlink {
+ rewriteToUseGot(ctxt, p, newprog)
+ }
+}
+
+// Rewrite p, if necessary, to access global data via the global offset table.
+func rewriteToUseGot(ctxt *obj.Link, p *obj.Prog, newprog obj.ProgAlloc) {
+ if p.As == obj.ADUFFCOPY || p.As == obj.ADUFFZERO {
+ // ADUFFxxx $offset
+ // becomes
+ // MOV runtime.duffxxx@GOT, REG_TMP
+ // ADD $offset, REG_TMP
+ // CALL REG_TMP
+ var sym *obj.LSym
+ if p.As == obj.ADUFFCOPY {
+ sym = ctxt.LookupABI("runtime.duffcopy", obj.ABIInternal)
+ } else {
+ sym = ctxt.LookupABI("runtime.duffzero", obj.ABIInternal)
+ }
+ offset := p.To.Offset
+ p.As = AMOV
+ p.From.Type = obj.TYPE_MEM
+ p.From.Name = obj.NAME_GOTREF
+ p.From.Sym = sym
+ p.To.Type = obj.TYPE_REG
+ p.To.Reg = REG_TMP
+ p.To.Name = obj.NAME_NONE
+ p.To.Offset = 0
+ p.To.Sym = nil
+
+ p1 := obj.Appendp(p, newprog)
+ p1.As = AADD
+ p1.From.Type = obj.TYPE_CONST
+ p1.From.Offset = offset
+ p1.To.Type = obj.TYPE_REG
+ p1.To.Reg = REG_TMP
+
+ p2 := obj.Appendp(p1, newprog)
+ p2.As = obj.ACALL
+ p2.To.Type = obj.TYPE_REG
+ p2.To.Reg = REG_TMP
+ }
+
+ // We only care about global data: NAME_EXTERN means a global
+ // symbol in the Go sense and p.Sym.Local is true for a few internally
+ // defined symbols.
+ if p.From.Type == obj.TYPE_ADDR && p.From.Name == obj.NAME_EXTERN && !p.From.Sym.Local() {
+ // MOV $sym, Rx becomes MOV sym@GOT, Rx
+ // MOV $sym+<off>, Rx becomes MOV sym@GOT, Rx; ADD <off>, Rx
+ if p.As != AMOV {
+ ctxt.Diag("don't know how to handle TYPE_ADDR in %v with -dynlink", p)
+ }
+ if p.To.Type != obj.TYPE_REG {
+ ctxt.Diag("don't know how to handle LD instruction to non-register in %v with -dynlink", p)
+ }
+ p.From.Type = obj.TYPE_MEM
+ p.From.Name = obj.NAME_GOTREF
+ if p.From.Offset != 0 {
+ q := obj.Appendp(p, newprog)
+ q.As = AADD
+ q.From.Type = obj.TYPE_CONST
+ q.From.Offset = p.From.Offset
+ q.To = p.To
+ p.From.Offset = 0
+ }
+
+ }
+
+ if p.GetFrom3() != nil && p.GetFrom3().Name == obj.NAME_EXTERN {
+ ctxt.Diag("don't know how to handle %v with -dynlink", p)
+ }
+
+ var source *obj.Addr
+ // MOVx sym, Ry becomes MOV sym@GOT, X31; MOVx (X31), Ry
+ // MOVx Ry, sym becomes MOV sym@GOT, X31; MOV Ry, (X31)
+ // An addition may be inserted between the two MOVs if there is an offset.
+ if p.From.Name == obj.NAME_EXTERN && !p.From.Sym.Local() {
+ if p.To.Name == obj.NAME_EXTERN && !p.To.Sym.Local() {
+ ctxt.Diag("cannot handle NAME_EXTERN on both sides in %v with -dynlink", p)
+ }
+ source = &p.From
+ } else if p.To.Name == obj.NAME_EXTERN && !p.To.Sym.Local() {
+ source = &p.To
+ } else {
+ return
+ }
+ if p.As == obj.ATEXT || p.As == obj.AFUNCDATA || p.As == obj.ACALL || p.As == obj.ARET || p.As == obj.AJMP {
+ return
+ }
+ if source.Sym.Type == objabi.STLSBSS {
+ return
+ }
+ if source.Type != obj.TYPE_MEM {
+ ctxt.Diag("don't know how to handle %v with -dynlink", p)
+ }
+ p1 := obj.Appendp(p, newprog)
+ p1.As = AMOV
+ p1.From.Type = obj.TYPE_MEM
+ p1.From.Sym = source.Sym
+ p1.From.Name = obj.NAME_GOTREF
+ p1.To.Type = obj.TYPE_REG
+ p1.To.Reg = REG_TMP
+
+ p2 := obj.Appendp(p1, newprog)
+ p2.As = p.As
+ p2.From = p.From
+ p2.To = p.To
+ if p.From.Name == obj.NAME_EXTERN {
+ p2.From.Reg = REG_TMP
+ p2.From.Name = obj.NAME_NONE
+ p2.From.Sym = nil
+ } else if p.To.Name == obj.NAME_EXTERN {
+ p2.To.Reg = REG_TMP
+ p2.To.Name = obj.NAME_NONE
+ p2.To.Sym = nil
+ } else {
+ return
+ }
+ obj.Nopout(p)
+
}
// addrToReg extracts the register from an Addr, handling special Addr.Names.
diff --git a/src/cmd/link/internal/riscv64/asm.go b/src/cmd/link/internal/riscv64/asm.go
index 6a4dd01240..a9583d21aa 100644
--- a/src/cmd/link/internal/riscv64/asm.go
+++ b/src/cmd/link/internal/riscv64/asm.go
@@ -20,7 +20,26 @@ import (
// fakeLabelName matches the RISCV_FAKE_LABEL_NAME from binutils.
const fakeLabelName = ".L0 "
-func gentext(ctxt *ld.Link, ldr *loader.Loader) {}
+func gentext(ctxt *ld.Link, ldr *loader.Loader) {
+ initfunc, addmoduledata := ld.PrepareAddmoduledata(ctxt)
+ if initfunc == nil {
+ return
+ }
+
+ // Emit the following function:
+ //
+ // go.link.addmoduledatainit:
+ // auipc a0, %pcrel_hi(local.moduledata)
+ // addi a0, %pcrel_lo(local.moduledata)
+ // j runtime.addmoduledata
+
+ sz := initfunc.AddSymRef(ctxt.Arch, ctxt.Moduledata, 0, objabi.R_RISCV_PCREL_ITYPE, 8)
+ initfunc.SetUint32(ctxt.Arch, sz-8, 0x00000517) // auipc a0, %pcrel_hi(local.moduledata)
+ initfunc.SetUint32(ctxt.Arch, sz-4, 0x00050513) // addi a0, %pcrel_lo(local.moduledata)
+
+ sz = initfunc.AddSymRef(ctxt.Arch, addmoduledata, 0, objabi.R_RISCV_JAL, 4)
+ initfunc.SetUint32(ctxt.Arch, sz-4, 0x0000006f) // j runtime.addmoduledata
+}
func findHI20Reloc(ldr *loader.Loader, s loader.Sym, val int64) *loader.Reloc {
outer := ldr.OuterSym(s)
diff --git a/src/internal/platform/supported.go b/src/internal/platform/supported.go
index a774247e6b..bad1a6c9c4 100644
--- a/src/internal/platform/supported.go
+++ b/src/internal/platform/supported.go
@@ -207,7 +207,7 @@ func BuildModeSupported(compiler, buildmode, goos, goarch string) bool {
case "plugin":
switch platform {
- case "linux/amd64", "linux/arm", "linux/arm64", "linux/386", "linux/loong64", "linux/s390x", "linux/ppc64le",
+ case "linux/amd64", "linux/arm", "linux/arm64", "linux/386", "linux/loong64", "linux/riscv64", "linux/s390x", "linux/ppc64le",
"android/amd64", "android/386",
"darwin/amd64", "darwin/arm64",
"freebsd/amd64":
diff --git a/src/runtime/asm_riscv64.s b/src/runtime/asm_riscv64.s
index 491635b1cf..231564aca2 100644
--- a/src/runtime/asm_riscv64.s
+++ b/src/runtime/asm_riscv64.s
@@ -542,6 +542,15 @@ TEXT runtime·goexit(SB),NOSPLIT|NOFRAME|TOPFRAME,$0-0
// traceback from goexit1 must hit code range of goexit
MOV ZERO, ZERO // NOP
+
+// This is called from .init_array and follows the platform, not the Go ABI.
+TEXT runtime·addmoduledata(SB),NOSPLIT,$0-0
+ // Use X31 as it is a scratch register in both the Go ABI and psABI.
+ MOV runtime·lastmoduledatap(SB), X31
+ MOV X10, moduledata_next(X31)
+ MOV X10, runtime·lastmoduledatap(SB)
+ RET
+
// func cgocallback(fn, frame unsafe.Pointer, ctxt uintptr)
// See cgocall.go for more details.
TEXT ·cgocallback(SB),NOSPLIT,$24-24
--
2.48.1.windows.1