Merge change 1714
* changes:
ACC ARM code gen: Implement local variables, function args
diff --git a/libacc/acc.cpp b/libacc/acc.cpp
index b27fce4..c8c0826 100644
--- a/libacc/acc.cpp
+++ b/libacc/acc.cpp
@@ -248,49 +248,57 @@
ARMCodeGenerator() {}
virtual ~ARMCodeGenerator() {}
- // The gnu ARM assembler prints the constants in little-endian,
- // but C hexidecimal constants are big-endian. We trick the
- // gnu assembler into putting out big-endian constants by
- // using the -mbig-endian flag when assembling.
-
/* returns address to patch with local variable size
*/
virtual int functionEntry(int argCount) {
fprintf(stderr, "functionEntry(%d);\n", argCount);
- /*
- 19 0000 E1A0C00D mov ip, sp
- 20 0004 E92DD800 stmfd sp!, {fp, ip, lr, pc}
- 21 0008 E24CB004 sub fp, ip, #4
- 22 000c E24DD008 sub sp, sp, #8
- */
- o4(0xE1A0C00D);
- o4(0xE92DD800);
- o4(0xE24CB004);
- return o4(0xE24DD008);
+ // 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!, {}
+ }
+ // sp -> arg0 arg1 ...
+ o4(0xE92D4800); // stmfd sp!, {fp, lr}
+ // sp, fp -> oldfp, retadr, arg0 arg1 ....
+ o4(0xE1A0B00D); // mov fp, sp
+ return o4(0xE24DD000); // sub sp, sp, # <local variables>
}
virtual void functionExit(int argCount, int localVariableAddress, int localVariableSize) {
fprintf(stderr, "functionExit(%d, %d, %d);\n", argCount, localVariableAddress, localVariableSize);
- /*
- 23 0010 E24BD00C sub sp, fp, #12
- 24 0014 E89DA800 ldmfd sp, {fp, sp, pc}
- */
- o4(0xE24BD00C);
- o4(0xE89DA800);
- if (localVariableSize < 0 || localVariableSize > 255-8) {
+ // Patch local variable allocation code:
+ if (localVariableSize < 0 || localVariableSize > 255) {
error("LocalVariableSize");
}
- *(char*) (localVariableAddress) = localVariableSize + 8;
+ *(char*) (localVariableAddress) = localVariableSize;
+
+ // sp -> locals .... fp -> oldfp, retadr, arg0, arg1, ...
+ o4(0xE1A0E00B); // mov lr, fp
+ o4(0xE59BB000); // ldr fp, [fp]
+ o4(0xE28ED004); // add sp, lr, #4
+ // sp -> retadr, arg0, ...
+ o4(0xE8BD4000); // ldmfd sp!, {lr}
+ // sp -> arg0 ....
+ if (argCount > 0) {
+ // We store the PC into the lr so we can adjust the sp before
+ // returning. (We need to pull off the registers we pushed
+ // earlier. We don't need to actually store them anywhere,
+ // just adjust the stack.
+ int regArgCount = argCount <= 4 ? argCount : 4;
+ o4(0xE28DD000 | (regArgCount << 2)); // add sp, sp, #argCount << 2
+ }
+ o4(0xE12FFF1E); // bx lr
}
/* load immediate value */
virtual void li(int t) {
fprintf(stderr, "li(%d);\n", t);
if (t >= 0 && t < 255) {
- o4(0xE3A00000 + t); // E3A00000 mov r0, #0
+ o4(0xE3A00000 + t); // mov r0, #0
} else if (t >= -256 && t < 0) {
// mvn means move constant ^ ~0
- o4(0xE3E00001 - t); // E3E00000 mvn r0, #0
+ o4(0xE3E00001 - t); // mvn r0, #0
} else {
o4(0xE51F0000); // ldr r0, .L3
o4(0xEA000000); // b .L99
@@ -307,12 +315,14 @@
/* l = 0: je, l == 1: jne */
virtual int gtst(bool l, int t) {
fprintf(stderr, "gtst(%d, %d);\n", l, t);
+ error("Unimplemented");
o(0x0fc085); /* test %eax, %eax, je/jne xxx */
return psym(0x84 + l, t);
}
virtual void gcmp(int op) {
fprintf(stderr, "gcmp(%d);\n", op);
+ error("Unimplemented");
#if 0
int t = decodeOp(op);
o(0xc139); /* cmp %eax,%ecx */
@@ -354,7 +364,7 @@
o4(0xE1E00000); // mvn r0, r0
break;
default:
- error("Unhandled op %d\n", op);
+ error("Unimplemented op %d\n", op);
break;
}
#if 0
@@ -387,37 +397,52 @@
virtual void loadEAXIndirect(bool isInt) {
fprintf(stderr, "loadEAXIndirect(%d);\n", isInt);
if (isInt)
- o(0x8b); /* mov (%eax), %eax */
+ o4(0xE5900000); // ldr r0, [r0]
else
- o(0xbe0f); /* movsbl (%eax), %eax */
- ob(0); /* add zero in code */
+ o4(0xE5D00000); // ldrb r0, [r0]
}
virtual void leaEAX(int ea) {
- fprintf(stderr, "leaEAX(%d);\n", ea);
-#if 0
- gmov(10, ea); /* leal EA, %eax */
-#endif
+ fprintf(stderr, "[!!! fixme !!!] leaEAX(%d);\n", ea);
+ error("Unimplemented");
+ if (ea < -4095 || ea > 4095) {
+ error("Offset out of range: %08x", ea);
+ }
+ o4(0xE59B0000 | (0x1fff & ea)); //ldr r0, [fp,#ea]
}
virtual void storeEAX(int ea) {
fprintf(stderr, "storeEAX(%d);\n", ea);
-#if 0
- gmov(6, ea); /* mov %eax, EA */
-#endif
+ int fpOffset = ea;
+ if (fpOffset < -4095 || fpOffset > 4095) {
+ error("Offset out of range: %08x", ea);
+ }
+ if (fpOffset < 0) {
+ o4(0xE50B0000 | (0xfff & (-fpOffset))); // str r0, [fp,#-ea]
+ } else {
+ o4(0xE58B0000 | (0xfff & fpOffset)); // str r0, [fp,#ea]
+ }
}
virtual void loadEAX(int ea) {
fprintf(stderr, "loadEAX(%d);\n", ea);
-#if 0
- gmov(8, ea); /* mov EA, %eax */
-#endif
+ int fpOffset = ea;
+ if (fpOffset < -4095 || fpOffset > 4095) {
+ error("Offset out of range: %08x", ea);
+ }
+ if (fpOffset < 0) {
+ o4(0xE51B0000 | (0xfff & (-fpOffset))); // ldr r0, [fp,#-ea]
+ } else {
+ o4(0xE59B0000 | (0xfff & fpOffset)); //ldr r0, [fp,#ea]
+ }
}
virtual void postIncrementOrDecrement(int n, int op) {
fprintf(stderr, "postIncrementOrDecrement(%d, %d);\n", n, op);
/* Implement post-increment or post decrement.
*/
+
+ error("Unimplemented");
#if 0
gmov(0, n); /* 83 ADD */
o(decodeOp(op));
@@ -459,7 +484,7 @@
virtual void callRelative(int t) {
fprintf(stderr, "callRelative(%d);\n", t);
int abs = t + getPC() + jumpOffset();
- fprintf(stderr, "abs=%d\n", abs);
+ fprintf(stderr, "abs=%d (0x08%x)\n", abs, abs);
if (t >= - (1 << 25) && t < (1 << 25)) {
o4(0xEB000000 | encodeAddress(t));
} else {