1 /* -*- Mode: C; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
2 /* This Source Code Form is subject to the terms of the Mozilla Public
3 * License, v. 2.0. If a copy of the MPL was not distributed with this
4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
5
6 // Implement shared vtbl methods.
7
8 #include "xptcprivate.h"
9 #include "xptiprivate.h"
10
11 // The Linux/PPC ABI (aka PPC/SYSV ABI) passes the first 8 integral
12 // parameters and the first 8 floating point parameters in registers
13 // (r3-r10 and f1-f8), no stack space is allocated for these by the
14 // caller. The rest of the parameters are passed in the callers stack
15 // area. The stack pointer has to retain 16-byte alignment, longlongs
16 // and doubles are aligned on 8-byte boundaries.
17
18 #define PARAM_BUFFER_COUNT 16
19 #define GPR_COUNT 8
20 #define FPR_COUNT 8
21
22 // PrepareAndDispatch() is called by SharedStub() and calls the actual method.
23 //
24 // - 'args[]' contains the arguments passed on stack
25 // - 'gprData[]' contains the arguments passed in integer registers
26 // - 'fprData[]' contains the arguments passed in floating point registers
27 //
28 // The parameters are mapped into an array of type 'nsXPTCMiniVariant'
29 // and then the method gets called.
30
31 extern "C" nsresult ATTRIBUTE_USED
PrepareAndDispatch(nsXPTCStubBase * self,uint32_t methodIndex,uint32_t * args,uint32_t * gprData,double * fprData)32 PrepareAndDispatch(nsXPTCStubBase* self,
33 uint32_t methodIndex,
34 uint32_t* args,
35 uint32_t *gprData,
36 double *fprData)
37 {
38 nsXPTCMiniVariant paramBuffer[PARAM_BUFFER_COUNT];
39 nsXPTCMiniVariant* dispatchParams = nullptr;
40 const nsXPTMethodInfo* info = nullptr;
41 uint32_t paramCount;
42 uint32_t i;
43 nsresult result = NS_ERROR_FAILURE;
44
45 NS_ASSERTION(self,"no self");
46
47 self->mEntry->GetMethodInfo(uint16_t(methodIndex), &info);
48 NS_ASSERTION(info,"no method info");
49 if (! info)
50 return NS_ERROR_UNEXPECTED;
51
52 paramCount = info->GetParamCount();
53
54 // setup variant array pointer
55 if(paramCount > PARAM_BUFFER_COUNT)
56 dispatchParams = new nsXPTCMiniVariant[paramCount];
57 else
58 dispatchParams = paramBuffer;
59
60 NS_ASSERTION(dispatchParams,"no place for params");
61 if (!dispatchParams)
62 return NS_ERROR_OUT_OF_MEMORY;
63
64 uint32_t* ap = args;
65 uint32_t gpr = 1; // skip one GPR register
66 uint32_t fpr = 0;
67 uint32_t tempu32;
68 uint64_t tempu64;
69
70 for(i = 0; i < paramCount; i++) {
71 const nsXPTParamInfo& param = info->GetParam(i);
72 const nsXPTType& type = param.GetType();
73 nsXPTCMiniVariant* dp = &dispatchParams[i];
74
75 if (!param.IsOut() && type == nsXPTType::T_DOUBLE) {
76 if (fpr < FPR_COUNT)
77 dp->val.d = fprData[fpr++];
78 else {
79 if ((uint32_t) ap & 4) ap++; // doubles are 8-byte aligned on stack
80 dp->val.d = *(double*) ap;
81 ap += 2;
82 }
83 continue;
84 }
85 else if (!param.IsOut() && type == nsXPTType::T_FLOAT) {
86 if (fpr < FPR_COUNT)
87 dp->val.f = (float) fprData[fpr++]; // in registers floats are passed as doubles
88 else
89 dp->val.f = *(float*) ap++;
90 continue;
91 }
92 else if (!param.IsOut() && (type == nsXPTType::T_I64
93 || type == nsXPTType::T_U64)) {
94 if (gpr & 1) gpr++; // longlongs are aligned in odd/even register pairs, eg. r5/r6
95 if ((gpr + 1) < GPR_COUNT) {
96 tempu64 = *(uint64_t*) &gprData[gpr];
97 gpr += 2;
98 }
99 else {
100 if ((uint32_t) ap & 4) ap++; // longlongs are 8-byte aligned on stack
101 tempu64 = *(uint64_t*) ap;
102 ap += 2;
103 }
104 }
105 else {
106 if (gpr < GPR_COUNT)
107 tempu32 = gprData[gpr++];
108 else
109 tempu32 = *ap++;
110 }
111
112 if(param.IsOut() || !type.IsArithmetic()) {
113 if (type == nsXPTType::T_JSVAL)
114 dp->val.p = *((void**) tempu32);
115 else
116 dp->val.p = (void*) tempu32;
117 continue;
118 }
119
120 switch(type) {
121 case nsXPTType::T_I8: dp->val.i8 = (int8_t) tempu32; break;
122 case nsXPTType::T_I16: dp->val.i16 = (int16_t) tempu32; break;
123 case nsXPTType::T_I32: dp->val.i32 = (int32_t) tempu32; break;
124 case nsXPTType::T_I64: dp->val.i64 = (int64_t) tempu64; break;
125 case nsXPTType::T_U8: dp->val.u8 = (uint8_t) tempu32; break;
126 case nsXPTType::T_U16: dp->val.u16 = (uint16_t) tempu32; break;
127 case nsXPTType::T_U32: dp->val.u32 = (uint32_t) tempu32; break;
128 case nsXPTType::T_U64: dp->val.u64 = (uint64_t) tempu64; break;
129 case nsXPTType::T_BOOL: dp->val.b = (bool) tempu32; break;
130 case nsXPTType::T_CHAR: dp->val.c = (char) tempu32; break;
131 case nsXPTType::T_WCHAR: dp->val.wc = (wchar_t) tempu32; break;
132
133 default:
134 NS_ERROR("bad type");
135 break;
136 }
137 }
138
139 result = self->mOuter->CallMethod((uint16_t)methodIndex,
140 info,
141 dispatchParams);
142
143 if (dispatchParams != paramBuffer)
144 delete [] dispatchParams;
145
146 return result;
147 }
148
149 // Load r11 with the constant 'n' and branch to SharedStub().
150 //
151 // XXX Yes, it's ugly that we're relying on gcc's name-mangling here;
152 // however, it's quick, dirty, and'll break when the ABI changes on
153 // us, which is what we want ;-).
154
155
156 // gcc-3 version
157 //
158 // As G++3 ABI contains the length of the functionname in the mangled
159 // name, it is difficult to get a generic assembler mechanism like
160 // in the G++ 2.95 case.
161 // Create names would be like:
162 // _ZN14nsXPTCStubBase5Stub1Ev
163 // _ZN14nsXPTCStubBase6Stub12Ev
164 // _ZN14nsXPTCStubBase7Stub123Ev
165 // _ZN14nsXPTCStubBase8Stub1234Ev
166 // etc.
167 // Use assembler directives to get the names right...
168
169 # define STUB_ENTRY(n) \
170 __asm__ ( \
171 ".align 2 \n\t" \
172 ".if "#n" < 10 \n\t" \
173 ".globl _ZN14nsXPTCStubBase5Stub"#n"Ev \n\t" \
174 ".type _ZN14nsXPTCStubBase5Stub"#n"Ev,@function \n\n" \
175 "_ZN14nsXPTCStubBase5Stub"#n"Ev: \n\t" \
176 \
177 ".elseif "#n" < 100 \n\t" \
178 ".globl _ZN14nsXPTCStubBase6Stub"#n"Ev \n\t" \
179 ".type _ZN14nsXPTCStubBase6Stub"#n"Ev,@function \n\n" \
180 "_ZN14nsXPTCStubBase6Stub"#n"Ev: \n\t" \
181 \
182 ".elseif "#n" < 1000 \n\t" \
183 ".globl _ZN14nsXPTCStubBase7Stub"#n"Ev \n\t" \
184 ".type _ZN14nsXPTCStubBase7Stub"#n"Ev,@function \n\n" \
185 "_ZN14nsXPTCStubBase7Stub"#n"Ev: \n\t" \
186 \
187 ".else \n\t" \
188 ".err \"stub number "#n" >= 1000 not yet supported\"\n" \
189 ".endif \n\t" \
190 \
191 "li 11,"#n" \n\t" \
192 "b SharedStub@local \n" \
193 );
194
195 #define SENTINEL_ENTRY(n) \
196 nsresult nsXPTCStubBase::Sentinel##n() \
197 { \
198 NS_ERROR("nsXPTCStubBase::Sentinel called"); \
199 return NS_ERROR_NOT_IMPLEMENTED; \
200 }
201
202 #include "xptcstubsdef.inc"
203