summaryrefslogtreecommitdiffstats
path: root/src/runtime/time_windows_386.s
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-16 19:19:13 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-16 19:19:13 +0000
commitccd992355df7192993c666236047820244914598 (patch)
treef00fea65147227b7743083c6148396f74cd66935 /src/runtime/time_windows_386.s
parentInitial commit. (diff)
downloadgolang-1.21-ccd992355df7192993c666236047820244914598.tar.xz
golang-1.21-ccd992355df7192993c666236047820244914598.zip
Adding upstream version 1.21.8.upstream/1.21.8
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/runtime/time_windows_386.s')
-rw-r--r--src/runtime/time_windows_386.s84
1 files changed, 84 insertions, 0 deletions
diff --git a/src/runtime/time_windows_386.s b/src/runtime/time_windows_386.s
new file mode 100644
index 0000000..b8b636e
--- /dev/null
+++ b/src/runtime/time_windows_386.s
@@ -0,0 +1,84 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build !faketime
+
+#include "go_asm.h"
+#include "textflag.h"
+#include "time_windows.h"
+
+TEXT time·now(SB),NOSPLIT,$0-20
+ CMPB runtime·useQPCTime(SB), $0
+ JNE useQPC
+loop:
+ MOVL (_INTERRUPT_TIME+time_hi1), AX
+ MOVL (_INTERRUPT_TIME+time_lo), CX
+ MOVL (_INTERRUPT_TIME+time_hi2), DI
+ CMPL AX, DI
+ JNE loop
+
+ // w = DI:CX
+ // multiply by 100
+ MOVL $100, AX
+ MULL CX
+ IMULL $100, DI
+ ADDL DI, DX
+ // w*100 = DX:AX
+ MOVL AX, mono+12(FP)
+ MOVL DX, mono+16(FP)
+
+wall:
+ MOVL (_SYSTEM_TIME+time_hi1), CX
+ MOVL (_SYSTEM_TIME+time_lo), AX
+ MOVL (_SYSTEM_TIME+time_hi2), DX
+ CMPL CX, DX
+ JNE wall
+
+ // w = DX:AX
+ // convert to Unix epoch (but still 100ns units)
+ #define delta 116444736000000000
+ SUBL $(delta & 0xFFFFFFFF), AX
+ SBBL $(delta >> 32), DX
+
+ // nano/100 = DX:AX
+ // split into two decimal halves by div 1e9.
+ // (decimal point is two spots over from correct place,
+ // but we avoid overflow in the high word.)
+ MOVL $1000000000, CX
+ DIVL CX
+ MOVL AX, DI
+ MOVL DX, SI
+
+ // DI = nano/100/1e9 = nano/1e11 = sec/100, DX = SI = nano/100%1e9
+ // split DX into seconds and nanoseconds by div 1e7 magic multiply.
+ MOVL DX, AX
+ MOVL $1801439851, CX
+ MULL CX
+ SHRL $22, DX
+ MOVL DX, BX
+ IMULL $10000000, DX
+ MOVL SI, CX
+ SUBL DX, CX
+
+ // DI = sec/100 (still)
+ // BX = (nano/100%1e9)/1e7 = (nano/1e9)%100 = sec%100
+ // CX = (nano/100%1e9)%1e7 = (nano%1e9)/100 = nsec/100
+ // store nsec for return
+ IMULL $100, CX
+ MOVL CX, nsec+8(FP)
+
+ // DI = sec/100 (still)
+ // BX = sec%100
+ // construct DX:AX = 64-bit sec and store for return
+ MOVL $0, DX
+ MOVL $100, AX
+ MULL DI
+ ADDL BX, AX
+ ADCL $0, DX
+ MOVL AX, sec+0(FP)
+ MOVL DX, sec+4(FP)
+ RET
+useQPC:
+ JMP runtime·nowQPC(SB)
+ RET