Support malloc() on bare metal

Your Actually Portable Executables now contains a simple virtual memory
that works similarly to the Linux Kernel in the sense that it maps your
physical memory to negative addresses. This is needed to support mmap()
and malloc(). This functionality has zero code size impact. For example
the MODE=tiny LIFE.COM executable is still only 12KB in size.

The APE bootloader code has also been simplified to improve readibility
and further elevate the elegance by which we're able to support so many
platforms thereby enhancing verifiability so that we may engender trust
in this bootloading process.

ape/config.h

@@ -1,118 +0,0 @@
-#ifndef APE_CONFIG_H_
-#define APE_CONFIG_H_
-#include "ape/relocations.h"
-#include "libc/macros.h"
-
-/*
- * Post-Initialization Read-Only Code Size Threshold.
- *
- * An executable needs to have at least this much code, before the
- * linker adds non-mandatory 4kb alignments. The benefit is better
- * memory protection. The tradeoff is sparser binaries.
- */
-#ifndef APE_PIRO_THRESHOLD
-#ifdef CONFIG_DBG
-#define APE_PIRO_THRESHOLD 0x1000
-#else
-#define APE_PIRO_THRESHOLD 0x10000
-#endif
-#endif
-
-#ifndef METAL_STDIN
-#define METAL_STDIN COM1
-#endif
-#ifndef METAL_STDOUT
-#define METAL_STDOUT COM1
-#endif
-#ifndef METAL_STDERR
-#define METAL_STDERR COM1
-#endif
-
-#ifndef VIDYA_MODE
-#define VIDYA_MODE VIDYA_MODE_CGA
-#endif
-
-/* FPU Control Word (x87) Exception Masks
-   @see Intel Manual V1 §8.1.5
-
-       IM: Invalid Operation ───────────────┐
-       DM: Denormal Operand ───────────────┐│
-       ZM: Zero Divide ───────────────────┐││
-       OM: Overflow ─────────────────────┐│││
-       UM: Underflow ───────────────────┐││││
-       PM: Precision ──────────────────┐│││││
-      PC: Precision Control ────────┐  ││││││
-       {float,∅,double,long double} │  ││││││
-      RC: Rounding Control ───────┐ │  ││││││
-       {even, →-∞, →+∞, →0}       │┌┤  ││││││
-                                 ┌┤││  ││││││
-                                d││││rr││││││*/
-#define X87_NORMAL    0b000000000001101111111
-#define X87_DTOA      0b000000000001000000000
-#define X87_DTOA_MASK 0b000000000001100000000
-#ifndef X87_DEFAULT
-#define X87_DEFAULT X87_NORMAL
-#endif
-
-#ifndef UART_BAUD_RATE
-#define UART_BAUD_RATE 9600 /* bits per second ∈ [50,115200] */
-#endif
-#define UART_CONF_DLR (1843200 /*hz*/ / 16 /*wut*/ / (UART_BAUD_RATE))
-#ifndef UART_CONF_IIR
-/*                      ┌interrupt trigger level {1,4,8,14}
-                        │ ┌enable 64 byte fifo (UART 16750+)
-                        │ │ ┌select dma mode
-                        │ │ │┌clear transmit fifo
-                        │ │ ││┌clear receive fifo
-                        ├┐│ │││┌enable fifos*/
-#define UART_CONF_IIR 0b00000000
-#endif
-#ifndef UART_CONF_LCR
-/*                      ┌dlab: flips configuration mode state
-                        │┌enable break signal
-                        ││ ┌parity {none,odd,even,high,low}
-                        ││ │ ┌extra stop bit
-                        ││ │ │┌data word length (bits+5)
-                        ││┌┴┐│├┐*/
-#define UART_CONF_LCR 0b01000011
-#endif
-
-#define XLM(VAR)                            (XLM_BASE_REAL + XLM_##VAR)
-#define XLMV(VAR)                           (__xlm + XLM_##VAR)
-#define XLM_BASE_REAL                       0x1000
-#define XLM_E820                            0
-#define XLM_E820_SIZE                       0x2000
-#define XLM_BIOS_DATA_AREA                  0x2000
-#define XLM_BIOS_DATA_AREA_SIZE             256
-#define XLM_DRIVE_BASE_TABLE                0x2200 /* drive values are contiguous */
-#define XLM_DRIVE_BASE_TABLE_SIZE           11
-#define XLM_DRIVE_TYPE                      0x220b
-#define XLM_DRIVE_TYPE_SIZE                 1
-#define XLM_DRIVE_LAST_SECTOR               0x220c /* 1-based inclusive, e.g. 18 */
-#define XLM_DRIVE_LAST_SECTOR_SIZE          1
-#define XLM_DRIVE_LAST_CYLINDER             0x220d /* 0-based incl, e.g. 79 */
-#define XLM_DRIVE_LAST_CYLINDER_SIZE        2
-#define XLM_DRIVE_ATTACHED                  0x220f
-#define XLM_DRIVE_ATTACHED_SIZE             1
-#define XLM_DRIVE_LAST_HEAD                 0x2210 /* 0-based inclusive, e.g. 1 */
-#define XLM_DRIVE_LAST_HEAD_SIZE            1
-#define XLM_DRIVE                           0x2211
-#define XLM_DRIVE_SIZE                      1
-#define XLM_HAVEEXTMEMKB                    0x2212
-#define XLM_HAVEEXTMEMKB_SIZE               4
-#define XLM_VIDEO_POSITION_FAR_POINTER      0x2216 /* video cursor far pointer */
-#define XLM_VIDEO_POSITION_FAR_POINTER_SIZE 4
-#define XLM_PAGE_TABLE_STACK_POINTER        0x2220
-#define XLM_PAGE_TABLE_STACK_POINTER_SIZE   8
-#define XLM_BADIDT                          0x2230
-#define XLM_BADIDT_SIZE                     6
-#define XLM_LOADSTATE                       0x2240
-#define XLM_LOADSTATE_SIZE                  8
-#define XLM_SIZE                            ROUNDUP(XLM_LOADSTATE + XLM_LOADSTATE_SIZE, 0x1000)
-#define IMAGE_BASE_REAL                     (XLM_BASE_REAL + XLM_SIZE)
-
-#if !defined(__LINKER__) && !defined(__ASSEMBLER__)
-extern char __xlm[XLM_SIZE];
-#endif /* !defined(__LINKER__) && !defined(__ASSEMBLER__) */
-
-#endif /* APE_CONFIG_H_ */