From: Michael Hudson-Doyle <michael.hudson@canonical.com>
Date: Thu, 29 Oct 2015 23:36:08 +0000 (+1300)
Subject: cmd/internal/obj, cmd/link, runtime: use a larger stack frame on ppc64
X-Git-Tag: go1.6beta1~490
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=c83c8065355c7ccef33eb0ebc870bf648d3d89cb;p=gostls13.git

cmd/internal/obj, cmd/link, runtime: use a larger stack frame on ppc64

The larger stack frames causes the nosplit stack to overflow so the next change
increases the stackguard.

Change-Id: Ib2b4f24f0649eb1d13e3a58d265f13d1b6cc9bf9
Reviewed-on: https://go-review.googlesource.com/15964
Reviewed-by: Russ Cox <rsc@golang.org>
---

diff --git a/src/cmd/internal/obj/link.go b/src/cmd/internal/obj/link.go
index 8ebb2f4c62..c1f2260e76 100644
--- a/src/cmd/internal/obj/link.go
+++ b/src/cmd/internal/obj/link.go
@@ -585,6 +585,10 @@ func (ctxt *Link) FixedFrameSize() int64 {
 	switch ctxt.Arch.Thechar {
 	case '6', '8':
 		return 0
+	case '9':
+		// PIC code on ppc64le requires 32 bytes of stack, and it's easier to
+		// just use that much stack always on ppc64x.
+		return int64(4 * ctxt.Arch.Ptrsize)
 	default:
 		return int64(ctxt.Arch.Ptrsize)
 	}
diff --git a/src/cmd/link/internal/ld/link.go b/src/cmd/link/internal/ld/link.go
index a9ea2d9589..73d23c6cf0 100644
--- a/src/cmd/link/internal/ld/link.go
+++ b/src/cmd/link/internal/ld/link.go
@@ -168,6 +168,10 @@ func (ctxt *Link) FixedFrameSize() int64 {
 	switch ctxt.Arch.Thechar {
 	case '6', '8':
 		return 0
+	case '9':
+		// PIC code on ppc64le requires 32 bytes of stack, and it's easier to
+		// just use that much stack always on ppc64x.
+		return int64(4 * ctxt.Arch.Ptrsize)
 	default:
 		return int64(ctxt.Arch.Ptrsize)
 	}
diff --git a/src/runtime/asm_ppc64x.h b/src/runtime/asm_ppc64x.h
index a2d2e5beaf..a413df6488 100644
--- a/src/runtime/asm_ppc64x.h
+++ b/src/runtime/asm_ppc64x.h
@@ -18,14 +18,8 @@
 // with arguments (the arguments should be stored at FIXED_FRAME+0(R1),
 // FIXED_FRAME+8(R1) etc) and some other low-level places.
 //
-// The reason for using a constant is when code is compiled as PIC on ppc64le
-// the fixed part of the stack is 32 bytes large (although PIC is not actually
-// supported yet).
+// The reason for using a constant is to make supporting PIC easier (although
+// we only support PIC on ppc64le which has a minimum 32 bytes of stack frame,
+// and currently always use that much, PIC on ppc64 would need to use 48).
 
-#ifdef GOARCH_ppc64
-#define FIXED_FRAME 8
-#endif
-
-#ifdef GOARCH_ppc64le
-#define FIXED_FRAME 8
-#endif
+#define FIXED_FRAME 32
diff --git a/src/runtime/asm_ppc64x.s b/src/runtime/asm_ppc64x.s
index 6f1191be02..5f5a658562 100644
--- a/src/runtime/asm_ppc64x.s
+++ b/src/runtime/asm_ppc64x.s
@@ -74,8 +74,11 @@ nocgo:
 	MOVDU	R3, -8(R1)
 	MOVDU	R0, -8(R1)
 	MOVDU	R0, -8(R1)
+	MOVDU	R0, -8(R1)
+	MOVDU	R0, -8(R1)
+	MOVDU	R0, -8(R1)
 	BL	runtime·newproc(SB)
-	ADD	$24, R1
+	ADD	$(16+FIXED_FRAME), R1
 
 	// start this M
 	BL	runtime·mstart(SB)
@@ -174,6 +177,9 @@ TEXT runtime·mcall(SB), NOSPLIT|NOFRAME, $0-8
 	MOVD	(g_sched+gobuf_sp)(g), R1	// sp = m->g0->sched.sp
 	MOVDU	R3, -8(R1)
 	MOVDU	R0, -8(R1)
+	MOVDU	R0, -8(R1)
+	MOVDU	R0, -8(R1)
+	MOVDU	R0, -8(R1)
 	BL	(CTR)
 	BR	runtime·badmcall2(SB)
 
diff --git a/src/runtime/internal/sys/arch_ppc64.go b/src/runtime/internal/sys/arch_ppc64.go
index fca31c28d0..3aa07e1f56 100644
--- a/src/runtime/internal/sys/arch_ppc64.go
+++ b/src/runtime/internal/sys/arch_ppc64.go
@@ -12,7 +12,7 @@ const (
 	PCQuantum     = 4
 	Int64Align    = 8
 	HugePageSize  = 0
-	MinFrameSize  = 8
+	MinFrameSize  = 32
 )
 
 type Uintreg uint64
diff --git a/src/runtime/internal/sys/arch_ppc64le.go b/src/runtime/internal/sys/arch_ppc64le.go
index 586a954a0c..0f02f0bf3c 100644
--- a/src/runtime/internal/sys/arch_ppc64le.go
+++ b/src/runtime/internal/sys/arch_ppc64le.go
@@ -12,7 +12,7 @@ const (
 	PCQuantum     = 4
 	Int64Align    = 8
 	HugePageSize  = 0
-	MinFrameSize  = 8
+	MinFrameSize  = 32
 )
 
 type Uintreg uint64