runtime: fix tv_sec handling for netbsd/386

On netbsd/386, tv_sec is a 64-bit integer for both timeval and timespec.
Fix the time handling code so that it works correctly.

R=golang-dev, rsc, m4dh4tt3r
CC=golang-dev
https://golang.org/cl/6256056

diff --git a/src/pkg/runtime/sys_netbsd_386.s b/src/pkg/runtime/sys_netbsd_386.s
index d8b422ea2aa90d942c53036a7e755f5b578f4c81..8b5d201e6b10293995296098e21e734fc275c836 100644 (file)
--- a/src/pkg/runtime/sys_netbsd_386.s
+++ b/src/pkg/runtime/sys_netbsd_386.s
@@ -27,15 +27,16 @@ TEXT runtime·write(SB),7,$-4
        INT     $0x80
        RET
 
-TEXT runtime·usleep(SB),7,$20
+TEXT runtime·usleep(SB),7,$24
        MOVL    $0, DX
        MOVL    usec+0(FP), AX
        MOVL    $1000000, CX
        DIVL    CX
-       MOVL    AX, 12(SP)              // tv_sec
+       MOVL    AX, 12(SP)              // tv_sec - l32
+       MOVL    $0, 16(SP)              // tv_sec - h32
        MOVL    $1000, AX
        MULL    DX
-       MOVL    AX, 16(SP)              // tv_nsec
+       MOVL    AX, 20(SP)              // tv_nsec
 
        MOVL    $0, 0(SP)
        LEAL    12(SP), AX
@@ -94,12 +95,13 @@ TEXT time·now(SB), 7, $32
        MOVL    $0, 8(SP)               // arg 2 - tzp
        MOVL    $418, AX                // sys_gettimeofday
        INT     $0x80
-       MOVL    12(SP), AX              // sec
-       MOVL    16(SP), BX              // usec
 
-       // sec is in AX, usec in BX
+       MOVL    12(SP), AX              // sec - l32
        MOVL    AX, sec+0(FP)
-       MOVL    $0, sec+4(FP)
+       MOVL    16(SP), AX              // sec - h32
+       MOVL    AX, sec+4(FP)
+
+       MOVL    20(SP), BX              // usec - should not exceed 999999
        IMULL   $1000, BX
        MOVL    BX, nsec+8(FP)
        RET
@@ -112,16 +114,18 @@ TEXT runtime·nanotime(SB),7,$32
        MOVL    $0, 8(SP)               // arg 2 - tzp
        MOVL    $418, AX                // sys_gettimeofday
        INT     $0x80
-       MOVL    12(SP), AX              // sec
-       MOVL    16(SP), BX              // usec
 
-       // sec is in AX, usec in BX
-       // convert to DX:AX nsec
-       MOVL    $1000000000, CX
-       MULL    CX
+       MOVL    16(SP), CX              // sec - h32
+       IMULL   $1000000000, CX
+
+       MOVL    12(SP), AX              // sec - l32
+       MOVL    $1000000000, BX
+       MULL    BX                      // result in dx:ax
+
+       MOVL    20(SP), BX              // usec
        IMULL   $1000, BX
        ADDL    BX, AX
-       ADCL    $0, DX
+       ADCL    CX, DX                  // add high bits with carry
 
        MOVL    ret+0(FP), DI
        MOVL    AX, 0(DI)