bug in stack size in arm.

stack is off by one if calling
through reflect.Call

R=rsc
CC=golang-dev
https://golang.org/cl/2400041

diff --git a/src/pkg/runtime/arm/asm.s b/src/pkg/runtime/arm/asm.s
index 1144ff2a17d075f23032251830229184f120376a..68d5f721c0a83216108fb51ab5338b30474e1c17 100644 (file)
--- a/src/pkg/runtime/arm/asm.s
+++ b/src/pkg/runtime/arm/asm.s
@@ -94,7 +94,7 @@ TEXT  breakpoint(SB),7,$0
 // uintptr gosave(Gobuf*)
 // save state in Gobuf; setjmp
 TEXT gosave(SB), 7, $-4
-       MOVW    0(FP), R0
+       MOVW    0(FP), R0               // gobuf
        MOVW    SP, gobuf_sp(R0)
        MOVW    LR, gobuf_pc(R0)
        MOVW    g, gobuf_g(R0)
@@ -104,7 +104,7 @@ TEXT gosave(SB), 7, $-4
 // void gogo(Gobuf*, uintptr)
 // restore state from Gobuf; longjmp
 TEXT   gogo(SB), 7, $-4
-       MOVW    0(FP), R1                       // gobuf
+       MOVW    0(FP), R1               // gobuf
        MOVW    4(FP), R0               // return 2nd arg
        MOVW    gobuf_g(R1), g
        MOVW    0(g), R2                // make sure g != nil
@@ -116,12 +116,14 @@ TEXT      gogo(SB), 7, $-4
 // (call fn, returning to state in Gobuf)
 // using frame size $-4 means do not save LR on stack.
 TEXT gogocall(SB), 7, $-4
-       MOVW    0(FP), R0
+       MOVW    0(FP), R0               // gobuf
        MOVW    4(FP), R1               // fn
+       MOVW    8(FP), R2               // fp offset
        MOVW    gobuf_g(R0), g
-       MOVW    0(g), R2                // make sure g != nil
+       MOVW    0(g), R3                // make sure g != nil
        MOVW    gobuf_sp(R0), SP        // restore SP
        MOVW    gobuf_pc(R0), LR
+       SUB     R2, SP
        MOVW    R1, PC
 
 /*
@@ -179,15 +181,15 @@ TEXT reflect·call(SB), 7, $-4
        // If it turns out that f needs a larger frame than
        // the default stack, f's usual stack growth prolog will
        // allocate a new segment (and recopy the arguments).
-       MOVW    4(SP), R0       // fn
-       MOVW    8(SP), R1       // arg frame
-       MOVW    12(SP), R2      // arg size
+       MOVW    4(SP), R0                       // fn
+       MOVW    8(SP), R1                       // arg frame
+       MOVW    12(SP), R2                      // arg size
 
-       MOVW    R0, m_morepc(m) // f's PC
-       MOVW    R1, m_morefp(m) // argument frame pointer
-       MOVW    R2, m_moreargs(m)       // f's argument size
+       MOVW    R0, m_morepc(m)                 // f's PC
+       MOVW    R1, m_morefp(m)                 // argument frame pointer
+       MOVW    R2, m_moreargs(m)               // f's argument size
        MOVW    $1, R3
-       MOVW    R3, m_moreframe(m)      // f's frame size
+       MOVW    R3, m_moreframe(m)              // f's frame size
 
        // Call newstack on m's scheduling stack.
        MOVW    m_g0(m), g

diff --git a/src/pkg/runtime/proc.c b/src/pkg/runtime/proc.c
index 9483e4c2904c2a5db7e43cd4f446dbfa6fa2be07..3688a1c235973cdc1b46a4bf2dcb81d5a6de17c2 100644 (file)
--- a/src/pkg/runtime/proc.c
+++ b/src/pkg/runtime/proc.c
@@ -528,7 +528,7 @@ scheduler(void)
        m->curg = gp;
        gp->m = m;
        if(gp->sched.pc == (byte*)goexit)       // kickoff
-               gogocall(&gp->sched, (void(*)(void))gp->entry);
+               gogocall(&gp->sched, (void(*)(void))gp->entry, 0);
        gogo(&gp->sched, 1);
 }
 
@@ -797,7 +797,7 @@ newstack(void)
        label.sp = sp;
        label.pc = (byte*)·lessstack;
        label.g = m->curg;
-       gogocall(&label, m->morepc);
+       gogocall(&label, m->morepc, 4);
 
        *(int32*)345 = 123;     // never return
 }

diff --git a/src/pkg/runtime/runtime.h b/src/pkg/runtime/runtime.h
index 88f53e2a2efe722ceb06269ff0cb90e613d42d52..15e846bd1b6b7b0eb1ba924b5530bece41c38e3d 100644 (file)
--- a/src/pkg/runtime/runtime.h
+++ b/src/pkg/runtime/runtime.h
@@ -377,7 +377,7 @@ int32       charntorune(int32*, uint8*, int32);
  * very low level c-called
  */
 void   gogo(Gobuf*, uintptr);
-void   gogocall(Gobuf*, void(*)(void));
+void   gogocall(Gobuf*, void(*)(void), int64);
 uintptr        gosave(Gobuf*);
 void   ·lessstack(void);
 void   goargs(void);