From: Russ Cox <rsc@golang.org>
Date: Wed, 6 Mar 2013 20:03:04 +0000 (-0500)
Subject: runtime: change amd64 startup convention
X-Git-Tag: go1.1rc2~674
X-Git-Url: http://www.git.cypherpunks.su/?a=commitdiff_plain;h=36b414f6397cadffab1a945eed645a3213f39d8a;p=gostls13.git

runtime: change amd64 startup convention

Now the default startup is that the program begins at _rt0_amd64_$GOOS,
which sets DI = argc, SI = argv and jumps to _rt0_amd64.

This makes the _rt0_amd64 entry match the expected semantics for
the standard C "main" function, which we can now provide for use when
linking against a standard C library.

R=golang-dev, devon.odell, minux.ma
CC=golang-dev
https://golang.org/cl/7525043
---

diff --git a/src/pkg/runtime/asm_amd64.s b/src/pkg/runtime/asm_amd64.s
index 696befd6e4..a671f39925 100644
--- a/src/pkg/runtime/asm_amd64.s
+++ b/src/pkg/runtime/asm_amd64.s
@@ -6,8 +6,8 @@
 
 TEXT _rt0_amd64(SB),7,$-8
 	// copy arguments forward on an even stack
-	MOVQ	0(DI), AX		// argc
-	LEAQ	8(DI), BX		// argv
+	MOVQ	DI, AX		// argc
+	MOVQ	SI, BX		// argv
 	SUBQ	$(4*8+7), SP		// 2args 2auto
 	ANDQ	$~15, SP
 	MOVQ	AX, 16(SP)
diff --git a/src/pkg/runtime/rt0_darwin_amd64.s b/src/pkg/runtime/rt0_darwin_amd64.s
index 4cfab58764..45e69a0159 100644
--- a/src/pkg/runtime/rt0_darwin_amd64.s
+++ b/src/pkg/runtime/rt0_darwin_amd64.s
@@ -2,9 +2,12 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Darwin and Linux use the same linkage to main
-
 TEXT _rt0_amd64_darwin(SB),7,$-8
+	LEAQ	8(SP), SI // argv
+	MOVQ	0(SP), DI // argc
+	MOVQ	$main(SB), AX
+	JMP	AX
+
+TEXT main(SB),7,$-8
 	MOVQ	$_rt0_amd64(SB), AX
-	MOVQ	SP, DI
 	JMP	AX
diff --git a/src/pkg/runtime/rt0_freebsd_amd64.s b/src/pkg/runtime/rt0_freebsd_amd64.s
index 5d2eeeefff..e6c6fb9cac 100644
--- a/src/pkg/runtime/rt0_freebsd_amd64.s
+++ b/src/pkg/runtime/rt0_freebsd_amd64.s
@@ -2,8 +2,12 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Darwin and Linux use the same linkage to main
-
 TEXT _rt0_amd64_freebsd(SB),7,$-8
-	MOVQ	$_rt0_amd64(SB), DX
-	JMP	DX
+	LEAQ	8(DI), SI // argv
+	MOVQ	0(DI), DI // argc
+	MOVQ	$main(SB), AX
+	JMP	AX
+
+TEXT main(SB),7,$-8
+	MOVQ	$_rt0_amd64(SB), AX
+	JMP	AX
diff --git a/src/pkg/runtime/rt0_linux_amd64.s b/src/pkg/runtime/rt0_linux_amd64.s
index dac9ae181b..dfc9c0421b 100644
--- a/src/pkg/runtime/rt0_linux_amd64.s
+++ b/src/pkg/runtime/rt0_linux_amd64.s
@@ -2,9 +2,12 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// Darwin and Linux use the same linkage to main
-
 TEXT _rt0_amd64_linux(SB),7,$-8
+	LEAQ	8(SP), SI // argv
+	MOVQ	0(SP), DI // argc
+	MOVQ	$main(SB), AX
+	JMP	AX
+
+TEXT main(SB),7,$-8
 	MOVQ	$_rt0_amd64(SB), AX
-	MOVQ	SP, DI
 	JMP	AX
diff --git a/src/pkg/runtime/rt0_netbsd_amd64.s b/src/pkg/runtime/rt0_netbsd_amd64.s
index 85482b98db..245a4c0f9b 100644
--- a/src/pkg/runtime/rt0_netbsd_amd64.s
+++ b/src/pkg/runtime/rt0_netbsd_amd64.s
@@ -2,7 +2,12 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-TEXT _rt0_amd64_netbsd(SB),7,$-8
-	MOVQ	$_rt0_amd64(SB), DX
-	MOVQ	SP, DI
-	JMP	DX
+TEXT _rt0_amd64_openbsd(SB),7,$-8
+	LEAQ	8(SP), SI // argv
+	MOVQ	0(SP), DI // argc
+	MOVQ	$main(SB), AX
+	JMP	AX
+
+TEXT main(SB),7,$-8
+	MOVQ	$_rt0_amd64(SB), AX
+	JMP	AX
diff --git a/src/pkg/runtime/rt0_openbsd_amd64.s b/src/pkg/runtime/rt0_openbsd_amd64.s
index e7fce59696..245a4c0f9b 100644
--- a/src/pkg/runtime/rt0_openbsd_amd64.s
+++ b/src/pkg/runtime/rt0_openbsd_amd64.s
@@ -3,6 +3,11 @@
 // license that can be found in the LICENSE file.
 
 TEXT _rt0_amd64_openbsd(SB),7,$-8
-	MOVQ	$_rt0_amd64(SB), DX
-	MOVQ	SP, DI
-	JMP	DX
+	LEAQ	8(SP), SI // argv
+	MOVQ	0(SP), DI // argc
+	MOVQ	$main(SB), AX
+	JMP	AX
+
+TEXT main(SB),7,$-8
+	MOVQ	$_rt0_amd64(SB), AX
+	JMP	AX
diff --git a/src/pkg/runtime/rt0_plan9_amd64.s b/src/pkg/runtime/rt0_plan9_amd64.s
index 2b1fa2ae1d..16e5e82b75 100644
--- a/src/pkg/runtime/rt0_plan9_amd64.s
+++ b/src/pkg/runtime/rt0_plan9_amd64.s
@@ -2,9 +2,10 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-TEXT _rt0_amd64_plan9(SB),7, $0
+TEXT _rt0_amd64_plan9(SB),7,$-8
+	LEAQ	8(SP), SI // argv
+	MOVQ	0(SP), DI // argc
 	MOVQ	$_rt0_amd64(SB), AX
-	MOVQ	SP, DI
 	JMP	AX
 
 DATA runtime·isplan9(SB)/4, $1
diff --git a/src/pkg/runtime/rt0_windows_amd64.s b/src/pkg/runtime/rt0_windows_amd64.s
index dc1408adc3..4fc61dc687 100644
--- a/src/pkg/runtime/rt0_windows_amd64.s
+++ b/src/pkg/runtime/rt0_windows_amd64.s
@@ -4,9 +4,14 @@
 
 #include "zasm_GOOS_GOARCH.h"
 
-TEXT	_rt0_amd64_windows(SB),7,$-8
+TEXT _rt0_amd64_darwin(SB),7,$-8
+	LEAQ	8(SP), SI // argv
+	MOVQ	0(SP), DI // argc
+	MOVQ	$main(SB), AX
+	JMP	AX
+
+TEXT main(SB),7,$-8
 	MOVQ	$_rt0_amd64(SB), AX
-	MOVQ	SP, DI
 	JMP	AX
 
 DATA  runtime·iswindows(SB)/4, $1