From: Mauri de Souza Meneguzzo <mauri870@gmail.com>
Date: Thu, 2 Nov 2023 22:15:03 +0000 (+0000)
Subject: runtime: add crash stack support for mips64x
X-Git-Tag: go1.22rc1~424
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=7dd94371339866b5809da2ad89b9c0b49b569ac5;p=gostls13.git

runtime: add crash stack support for mips64x

Change-Id: I240ea7dd6430f4c89cfdadbfa790e4a70a4fd79d
GitHub-Last-Rev: 585742b5eebad7c03ec313b590e2171491b78b37
GitHub-Pull-Request: golang/go#63905
Reviewed-on: https://go-review.googlesource.com/c/go/+/539295
Reviewed-by: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Heschi Kreinick <heschi@google.com>
Run-TryBot: Mauri de Souza Meneguzzo <mauri870@gmail.com>
---

diff --git a/src/runtime/asm.s b/src/runtime/asm.s
index 81d3bfbb8a..012a6a095d 100644
--- a/src/runtime/asm.s
+++ b/src/runtime/asm.s
@@ -15,6 +15,8 @@ TEXT ·mapinitnoop<ABIInternal>(SB),NOSPLIT,$0-0
 
 #ifndef GOARCH_amd64
 #ifndef GOARCH_arm64
+#ifndef GOARCH_mips64
+#ifndef GOARCH_mips64le
 #ifndef GOARCH_riscv64
 // stub to appease shared build mode.
 TEXT ·switchToCrashStack0<ABIInternal>(SB),NOSPLIT,$0-0
@@ -22,3 +24,5 @@ TEXT ·switchToCrashStack0<ABIInternal>(SB),NOSPLIT,$0-0
 #endif
 #endif
 #endif
+#endif
+#endif
diff --git a/src/runtime/asm_mips64x.s b/src/runtime/asm_mips64x.s
index 19592b5695..80cd87c4af 100644
--- a/src/runtime/asm_mips64x.s
+++ b/src/runtime/asm_mips64x.s
@@ -205,6 +205,29 @@ noswitch:
 	ADDV	$8, R29
 	JMP	(R4)
 
+// func switchToCrashStack0(fn func())
+TEXT runtime·switchToCrashStack0(SB), NOSPLIT, $0-8
+	MOVV	fn+0(FP), REGCTXT	// context register
+	MOVV	g_m(g), R2	// curm
+
+	// set g to gcrash
+	MOVV	$runtime·gcrash(SB), g	// g = &gcrash
+	CALL	runtime·save_g(SB)
+	MOVV	R2, g_m(g)	// g.m = curm
+	MOVV	g, m_g0(R2)	// curm.g0 = g
+
+	// switch to crashstack
+	MOVV	(g_stack+stack_hi)(g), R2
+	ADDV	$(-4*8), R2, R29
+
+	// call target function
+	MOVV	0(REGCTXT), R25
+	JAL	(R25)
+
+	// should never return
+	CALL	runtime·abort(SB)
+	UNDEF
+
 /*
  * support for morestack
  */
@@ -218,6 +241,13 @@ 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.
+	MOVV	R29, (g_sched+gobuf_sp)(g)
+	MOVV	R31, (g_sched+gobuf_pc)(g)
+	MOVV	R3, (g_sched+gobuf_lr)(g)
+	MOVV	REGCTXT, (g_sched+gobuf_ctxt)(g)
+
 	// Cannot grow scheduler stack (m->g0).
 	MOVV	g_m(g), R7
 	MOVV	m_g0(R7), R8
@@ -231,13 +261,6 @@ TEXT runtime·morestack(SB),NOSPLIT|NOFRAME,$0-0
 	JAL	runtime·badmorestackgsignal(SB)
 	JAL	runtime·abort(SB)
 
-	// Called from f.
-	// Set g->sched to context in f.
-	MOVV	R29, (g_sched+gobuf_sp)(g)
-	MOVV	R31, (g_sched+gobuf_pc)(g)
-	MOVV	R3, (g_sched+gobuf_lr)(g)
-	MOVV	REGCTXT, (g_sched+gobuf_ctxt)(g)
-
 	// Called from f.
 	// Set m->morebuf to f's caller.
 	MOVV	R3, (m_morebuf+gobuf_pc)(R7)	// f's caller's PC
diff --git a/src/runtime/proc.go b/src/runtime/proc.go
index 9b5f2e9a6d..7ed3068063 100644
--- a/src/runtime/proc.go
+++ b/src/runtime/proc.go
@@ -574,10 +574,10 @@ func switchToCrashStack(fn func()) {
 	abort()
 }
 
-const crashStackImplemented = GOARCH == "amd64" || GOARCH == "arm64" || GOARCH == "riscv64"
+const crashStackImplemented = GOARCH == "amd64" || GOARCH == "arm64" || GOARCH == "mips64" || GOARCH == "mips64le" || GOARCH == "riscv64"
 
 //go:noescape
-func switchToCrashStack0(func()) // in assembly
+func switchToCrashStack0(fn func()) // in assembly
 
 func lockedOSThread() bool {
 	gp := getg()