runtime: add support for crash stack on ppc64/ppc64le

Change-Id: I8d1011509c4f0f529e97055280606603747a2e1a
Reviewed-on: https://go-review.googlesource.com/c/go/+/541775
Reviewed-by: Mauri de Souza Meneguzzo <mauri870@gmail.com>
Reviewed-by: Paul Murphy <murp@ibm.com>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Run-TryBot: Joel Sing <joel@sing.id.au>

diff --git a/src/runtime/asm.s b/src/runtime/asm.s
index 012a6a095ddeca8ff4a3ef3fb43ddf372d6fafe8..45ba467806b2a49f193d16217b0363512801a66c 100644 (file)
--- a/src/runtime/asm.s
+++ b/src/runtime/asm.s
@@ -17,6 +17,8 @@ TEXT ·mapinitnoop<ABIInternal>(SB),NOSPLIT,$0-0
 #ifndef GOARCH_arm64
 #ifndef GOARCH_mips64
 #ifndef GOARCH_mips64le
+#ifndef GOARCH_ppc64
+#ifndef GOARCH_ppc64le
 #ifndef GOARCH_riscv64
 // stub to appease shared build mode.
 TEXT ·switchToCrashStack0<ABIInternal>(SB),NOSPLIT,$0-0
@@ -26,3 +28,5 @@ TEXT ·switchToCrashStack0<ABIInternal>(SB),NOSPLIT,$0-0
 #endif
 #endif
 #endif
+#endif
+#endif

diff --git a/src/runtime/asm_ppc64x.s b/src/runtime/asm_ppc64x.s
index 922c50dc4f0d375f796c838138e617c7f9ce73d0..ff9b736430cc2fa3930b868d4574bcec8192b7ec 100644 (file)
--- a/src/runtime/asm_ppc64x.s
+++ b/src/runtime/asm_ppc64x.s
@@ -284,6 +284,31 @@ noswitch:
 #endif
        RET
 
+// func switchToCrashStack0(fn func())
+TEXT runtime·switchToCrashStack0<ABIInternal>(SB), NOSPLIT, $0-8
+       MOVD    R3, R11                         // context register
+       MOVD    g_m(g), R3                      // curm
+
+       // set g to gcrash
+       MOVD    $runtime·gcrash(SB), g // g = &gcrash
+       CALL    runtime·save_g(SB)     // clobbers R31
+       MOVD    R3, g_m(g)                      // g.m = curm
+       MOVD    g, m_g0(R3)                     // curm.g0 = g
+
+       // switch to crashstack
+       MOVD    (g_stack+stack_hi)(g), R3
+       SUB     $(4*8), R3
+       MOVD    R3, R1
+
+       // call target function
+       MOVD    0(R11), R12                     // code pointer
+       MOVD    R12, CTR
+       BL      (CTR)
+
+       // should never return
+       CALL    runtime·abort(SB)
+       UNDEF
+
 /*
  * support for morestack
  */
@@ -297,6 +322,14 @@ noswitch:
 // calling the scheduler calling newm calling gc), so we must
 // record an argument size. For that purpose, it has no arguments.
 TEXT runtime·morestack(SB),NOSPLIT|NOFRAME,$0-0
+       // Called from f.
+       // Set g->sched to context in f.
+       MOVD    R1, (g_sched+gobuf_sp)(g)
+       MOVD    LR, R8
+       MOVD    R8, (g_sched+gobuf_pc)(g)
+       MOVD    R5, (g_sched+gobuf_lr)(g)
+       MOVD    R11, (g_sched+gobuf_ctxt)(g)
+
        // Cannot grow scheduler stack (m->g0).
        MOVD    g_m(g), R7
        MOVD    m_g0(R7), R8
@@ -312,14 +345,6 @@ TEXT runtime·morestack(SB),NOSPLIT|NOFRAME,$0-0
        BL      runtime·badmorestackgsignal(SB)
        BL      runtime·abort(SB)
 
-       // Called from f.
-       // Set g->sched to context in f.
-       MOVD    R1, (g_sched+gobuf_sp)(g)
-       MOVD    LR, R8
-       MOVD    R8, (g_sched+gobuf_pc)(g)
-       MOVD    R5, (g_sched+gobuf_lr)(g)
-       MOVD    R11, (g_sched+gobuf_ctxt)(g)
-
        // Called from f.
        // Set m->morebuf to f's caller.
        MOVD    R5, (m_morebuf+gobuf_pc)(R7)    // f's caller's PC

diff --git a/src/runtime/proc.go b/src/runtime/proc.go
index 6b13d3b2f6e16ff77855625374e06c16aa3cd27f..66d7da887e02834068b3cc04f100d993bddfe0fc 100644 (file)
--- a/src/runtime/proc.go
+++ b/src/runtime/proc.go
@@ -576,7 +576,7 @@ func switchToCrashStack(fn func()) {
        abort()
 }
 
-const crashStackImplemented = GOARCH == "amd64" || GOARCH == "arm64" || GOARCH == "mips64" || GOARCH == "mips64le" || GOARCH == "riscv64"
+const crashStackImplemented = GOARCH == "amd64" || GOARCH == "arm64" || GOARCH == "mips64" || GOARCH == "mips64le" || GOARCH == "ppc64" || GOARCH == "ppc64le" || GOARCH == "riscv64"
 
 //go:noescape
 func switchToCrashStack0(fn func()) // in assembly