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platform_system_core
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Align ARM stack pointer to an 8-byte boundary when calling functions. 

This is required by the ARM EABI standard.
This commit is contained in:
-b master 2009-06-17 19:13:52 -07:00
parent d7166ede3b
commit 422972cb12
2 changed files with 70 additions and 16 deletions
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77
libacc/acc.cpp
View File

@ -46,8 +46,11 @@
#define LOG_API(...) do {} while(0)
// #define LOG_API(...) fprintf (stderr, __VA_ARGS__)
// #define ENABLE_ARM_DISASSEMBLY
#define LOG_STACK(...) do {} while(0)
// #define LOG_STACK(...) fprintf (stderr, __VA_ARGS__)
// #define ENABLE_ARM_DISASSEMBLY
// #define PROVIDE_TRACE_CODEGEN
namespace acc {
@ -399,27 +402,38 @@ class Compiler : public ErrorSink {
class ARMCodeGenerator : public CodeGenerator {
public:
ARMCodeGenerator() {}
virtual ~ARMCodeGenerator() {}
/* returns address to patch with local variable size
*/
virtual int functionEntry(int argCount) {
LOG_API("functionEntry(%d);\n", argCount);
mStackUse = 0;
// sp -> arg4 arg5 ...
// Push our register-based arguments back on the stack
if (argCount > 0) {
int regArgCount = argCount <= 4 ? argCount : 4;
o4(0xE92D0000 | ((1 << argCount) - 1)); // stmfd sp!, {}
mStackUse += regArgCount * 4;
}
// sp -> arg0 arg1 ...
o4(0xE92D4800); // stmfd sp!, {fp, lr}
mStackUse += 2 * 4;
// sp, fp -> oldfp, retadr, arg0 arg1 ....
o4(0xE1A0B00D); // mov fp, sp
LOG_STACK("functionEntry: %d\n", mStackUse);
return o4(0xE24DD000); // sub sp, sp, # <local variables>
// We don't know how many local variables we are going to use,
// but we will round the allocation up to a multiple of
// STACK_ALIGNMENT, so it won't affect the stack alignment.
}
virtual void functionExit(int argCount, int localVariableAddress, int localVariableSize) {
LOG_API("functionExit(%d, %d, %d);\n", argCount, localVariableAddress, localVariableSize);
// Round local variable size up to a multiple of stack alignment
localVariableSize = ((localVariableSize + STACK_ALIGNMENT - 1) /
STACK_ALIGNMENT) * STACK_ALIGNMENT;
// Patch local variable allocation code:
if (localVariableSize < 0 || localVariableSize > 255) {
error("localVariables out of range: %d", localVariableSize);
@ -547,11 +561,6 @@ class Compiler : public ErrorSink {
error("Unimplemented op %d\n", op);
break;
}
#if 0
o(decodeOp(op));
if (op == OP_MOD)
o(0x92); /* xchg %edx, %eax */
#endif
}
virtual void clearR1() {
@ -562,11 +571,15 @@ class Compiler : public ErrorSink {
virtual void pushR0() {
LOG_API("pushR0();\n");
o4(0xE92D0001); // stmfd sp!,{r0}
mStackUse += 4;
LOG_STACK("pushR0: %d\n", mStackUse);
}
virtual void popR1() {
LOG_API("popR1();\n");
o4(0xE8BD0002); // ldmfd sp!,{r1}
mStackUse -= 4;
LOG_STACK("popR1: %d\n", mStackUse);
}
virtual void storeR0ToR1(bool isInt) {
@ -690,15 +703,31 @@ class Compiler : public ErrorSink {
virtual void endFunctionCallArguments(int a, int l) {
LOG_API("endFunctionCallArguments(0x%08x, %d);\n", a, l);
int argCount = l >> 2;
int argumentStackUse = l;
if (argCount > 0) {
int regArgCount = argCount > 4 ? 4 : argCount;
argumentStackUse -= regArgCount * 4;
o4(0xE8BD0000 | ((1 << regArgCount) - 1)); // ldmfd sp!,{}
}
mStackUse += argumentStackUse;
// Align stack.
int missalignment = mStackUse - ((mStackUse / STACK_ALIGNMENT)
* STACK_ALIGNMENT);
mStackAlignmentAdjustment = 0;
if (missalignment > 0) {
mStackAlignmentAdjustment = STACK_ALIGNMENT - missalignment;
}
l += mStackAlignmentAdjustment;
if (l < 0 || l > 0x3FC) {
error("L out of range for stack adjustment: 0x%08x", l);
}
* (int*) a = 0xE24DDF00 | (l >> 2); // sub sp, sp, #0 << 2
int argCount = l >> 2;
if (argCount > 0) {
int regArgCount = argCount > 4 ? 4 : argCount;
o4(0xE8BD0000 | ((1 << regArgCount) - 1)); // ldmfd sp!,{}
}
mStackUse += mStackAlignmentAdjustment;
LOG_STACK("endFunctionCallArguments mStackUse: %d, mStackAlignmentAdjustment %d\n",
mStackUse, mStackAlignmentAdjustment);
}
virtual int callForward(int symbol) {
@ -727,7 +756,7 @@ class Compiler : public ErrorSink {
LOG_API("callIndirect(%d);\n", l);
int argCount = l >> 2;
int poppedArgs = argCount > 4 ? 4 : argCount;
int adjustedL = l - (poppedArgs << 2);
int adjustedL = l - (poppedArgs << 2) + mStackAlignmentAdjustment;
if (adjustedL < 0 || adjustedL > 4096-4) {
error("l out of range for stack offset: 0x%08x", l);
}
@ -739,12 +768,15 @@ class Compiler : public ErrorSink {
LOG_API("adjustStackAfterCall(%d, %d);\n", l, isIndirect);
int argCount = l >> 2;
int stackArgs = argCount > 4 ? argCount - 4 : 0;
int stackUse = stackArgs + (isIndirect ? 1 : 0);
int stackUse = stackArgs + (isIndirect ? 1 : 0)
+ (mStackAlignmentAdjustment >> 2);
if (stackUse) {
if (stackUse < 0 || stackUse > 255) {
error("L out of range for stack adjustment: 0x%08x", l);
}
o4(0xE28DDF00 | stackUse); // add sp, sp, #stackUse << 2
mStackUse -= stackUse * 4;
LOG_STACK("adjustStackAfterCall: %d\n", mStackUse);
}
}
@ -858,6 +890,13 @@ class Compiler : public ErrorSink {
static int runtime_MOD(int a, int b) {
return b % a;
}
static const int STACK_ALIGNMENT = 8;
int mStackUse;
// This variable holds the amount we adjusted the stack in the most
// recent endFunctionCallArguments call. It's examined by the
// following adjustStackAfterCall call.
int mStackAlignmentAdjustment;
};
#endif // PROVIDE_ARM_CODEGEN
@ -981,7 +1020,9 @@ class Compiler : public ErrorSink {
if (isIndirect) {
l += 4;
}
oad(0xc481, l); /* add $xxx, %esp */
if (l > 0) {
oad(0xc481, l); /* add $xxx, %esp */
}
}
virtual int jumpOffset() {
@ -2315,8 +2356,7 @@ class Compiler : public ErrorSink {
} else {
pGen->callRelative(n - codeBuf.getPC() - pGen->jumpOffset());
}
if (l | (n == 1))
pGen->adjustStackAfterCall(l, n == 1);
pGen->adjustStackAfterCall(l, n == 1);
}
}
@ -3025,6 +3065,11 @@ void accGetPragmas(ACCscript* script, ACCsizei* actualStringCount,
script->compiler.getPragmas(actualStringCount, maxStringCount, strings);
}
extern "C"
void accDisassemble(ACCscript* script) {
script->compiler.disassemble(stderr);
}
} // namespace acc

9
libacc/tests/main.cpp
View File

@ -29,6 +29,11 @@ int run(MainPtr mainFunc, int argc, char** argv) {
return mainFunc(argc, argv);
}
// Private API for development:
extern "C"
void accDisassemble(ACCscript* script);
int main(int argc, char** argv) {
const char* inFile = NULL;
bool printListing;
@ -109,6 +114,10 @@ int main(int argc, char** argv) {
}
}
if (printListing) {
accDisassemble(script);
}
if (runResults) {
accGetScriptLabel(script, "main", (ACCvoid**) & mainPointer);