1 // Copyright 2021 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
4 5 // Macros for transitioning from the host ABI to Go ABI0.
6 //
7 // These save the frame pointer, so in general, functions that use
8 // these should have zero frame size to suppress the automatic frame
9 // pointer, though it's harmless to not do this.
10 11 #ifdef GOOS_windows
12 13 // REGS_HOST_TO_ABI0_STACK is the stack bytes used by
14 // PUSH_REGS_HOST_TO_ABI0.
15 #define REGS_HOST_TO_ABI0_STACK (28*8 + 8)
16 17 // PUSH_REGS_HOST_TO_ABI0 prepares for transitioning from
18 // the host ABI to Go ABI0 code. It saves all registers that are
19 // callee-save in the host ABI and caller-save in Go ABI0 and prepares
20 // for entry to Go.
21 //
22 // Save DI SI BP BX R12 R13 R14 R15 X6-X15 registers and the DF flag.
23 // Clear the DF flag for the Go ABI.
24 // MXCSR matches the Go ABI, so we don't have to set that,
25 // and Go doesn't modify it, so we don't have to save it.
26 #define PUSH_REGS_HOST_TO_ABI0() \
27 PUSHFQ \
28 CLD \
29 ADJSP $(REGS_HOST_TO_ABI0_STACK - 8) \
30 MOVQ DI, (0*0)(SP) \
31 MOVQ SI, (1*8)(SP) \
32 MOVQ BP, (2*8)(SP) \
33 MOVQ BX, (3*8)(SP) \
34 MOVQ R12, (4*8)(SP) \
35 MOVQ R13, (5*8)(SP) \
36 MOVQ R14, (6*8)(SP) \
37 MOVQ R15, (7*8)(SP) \
38 MOVUPS X6, (8*8)(SP) \
39 MOVUPS X7, (10*8)(SP) \
40 MOVUPS X8, (12*8)(SP) \
41 MOVUPS X9, (14*8)(SP) \
42 MOVUPS X10, (16*8)(SP) \
43 MOVUPS X11, (18*8)(SP) \
44 MOVUPS X12, (20*8)(SP) \
45 MOVUPS X13, (22*8)(SP) \
46 MOVUPS X14, (24*8)(SP) \
47 MOVUPS X15, (26*8)(SP)
48 49 #define POP_REGS_HOST_TO_ABI0() \
50 MOVQ (0*0)(SP), DI \
51 MOVQ (1*8)(SP), SI \
52 MOVQ (2*8)(SP), BP \
53 MOVQ (3*8)(SP), BX \
54 MOVQ (4*8)(SP), R12 \
55 MOVQ (5*8)(SP), R13 \
56 MOVQ (6*8)(SP), R14 \
57 MOVQ (7*8)(SP), R15 \
58 MOVUPS (8*8)(SP), X6 \
59 MOVUPS (10*8)(SP), X7 \
60 MOVUPS (12*8)(SP), X8 \
61 MOVUPS (14*8)(SP), X9 \
62 MOVUPS (16*8)(SP), X10 \
63 MOVUPS (18*8)(SP), X11 \
64 MOVUPS (20*8)(SP), X12 \
65 MOVUPS (22*8)(SP), X13 \
66 MOVUPS (24*8)(SP), X14 \
67 MOVUPS (26*8)(SP), X15 \
68 ADJSP $-(REGS_HOST_TO_ABI0_STACK - 8) \
69 POPFQ
70 71 #else
72 // SysV ABI
73 74 #define REGS_HOST_TO_ABI0_STACK (6*8)
75 76 // SysV MXCSR matches the Go ABI, so we don't have to set that,
77 // and Go doesn't modify it, so we don't have to save it.
78 // Both SysV and Go require DF to be cleared, so that's already clear.
79 // The SysV and Go frame pointer conventions are compatible.
80 #define PUSH_REGS_HOST_TO_ABI0() \
81 ADJSP $(REGS_HOST_TO_ABI0_STACK) \
82 MOVQ BP, (5*8)(SP) \
83 LEAQ (5*8)(SP), BP \
84 MOVQ BX, (0*8)(SP) \
85 MOVQ R12, (1*8)(SP) \
86 MOVQ R13, (2*8)(SP) \
87 MOVQ R14, (3*8)(SP) \
88 MOVQ R15, (4*8)(SP)
89 90 #define POP_REGS_HOST_TO_ABI0() \
91 MOVQ (0*8)(SP), BX \
92 MOVQ (1*8)(SP), R12 \
93 MOVQ (2*8)(SP), R13 \
94 MOVQ (3*8)(SP), R14 \
95 MOVQ (4*8)(SP), R15 \
96 MOVQ (5*8)(SP), BP \
97 ADJSP $-(REGS_HOST_TO_ABI0_STACK)
98 99 #endif
100