7842 - new directory organization

Baremetal is now the default build target and therefore has its sources
at the top-level. Baremetal programs build using the phase-2 Mu toolchain
that requires a Linux kernel. This phase-2 codebase which used to be at
the top-level is now under the linux/ directory. Finally, the phase-2 toolchain,
while self-hosting, has a way to bootstrap from a C implementation, which
is now stored in linux/bootstrap. The bootstrap C implementation uses some
literate programming tools that are now in linux/bootstrap/tools.

So the whole thing has gotten inverted. Each directory should build one
artifact and include the main sources (along with standard library). Tools
used for building it are relegated to sub-directories, even though those
tools are often useful in their own right, and have had lots of interesting
programs written using them.

A couple of things have gotten dropped in this process:
  - I had old ways to run on just a Linux kernel, or with a Soso kernel.
    No more.
  - I had some old tooling for running a single test at the cursor. I haven't
    used that lately. Maybe I'll bring it back one day.

The reorg isn't done yet. Still to do:
  - redo documentation everywhere. All the README files, all other markdown,
    particularly vocabulary.md.
  - clean up how-to-run comments at the start of programs everywhere
  - rethink what to do with the html/ directory. Do we even want to keep
    supporting it?

In spite of these shortcomings, all the scripts at the top-level, linux/
and linux/bootstrap are working. The names of the scripts also feel reasonable.
This is a good milestone to take stock at.

1 files changed, 0 insertions, 155 deletions

diff --git a/016index_addressing.cc b/016index_addressing.cc
deleted file mode 100644
index f6c6f2aa..00000000
--- a/016index_addressing.cc
+++ /dev/null
@@ -1,155 +0,0 @@
-//: operating on memory at the address provided by some register plus optional scale and offset
-
-:(code)
-void test_add_r32_to_mem_at_rm32_with_sib() {
-  Reg[EBX].i = 0x10;
-  Reg[EAX].i = 0x2000;
-  run(
-      "== code 0x1\n"
-      // op     ModR/M  SIB   displacement  immediate
-      "  01     1c      20                              \n"  // add EBX to *EAX
-      // ModR/M in binary: 00 (indirect mode) 011 (src EBX) 100 (dest in SIB)
-      // SIB in binary: 00 (scale 1) 100 (no index) 000 (base EAX)
-      "== data 0x2000\n"
-      "01 00 00 00\n"  // 1
-  );
-  CHECK_TRACE_CONTENTS(
-      "run: add EBX to r/m32\n"
-      "run: effective address is initially 0x00002000 (EAX)\n"
-      "run: effective address is 0x00002000\n"
-      "run: storing 0x00000011\n"
-  );
-}
-
-:(before "End Mod 0 Special-cases(addr)")
-case 4:  // exception: mod 0b00 rm 0b100 => incoming SIB (scale-index-base) byte
-  addr = effective_address_from_sib(mod);
-  break;
-:(code)
-uint32_t effective_address_from_sib(uint8_t mod) {
-  const uint8_t sib = next();
-  const uint8_t base = sib&0x7;
-  uint32_t addr = 0;
-  if (base != EBP || mod != 0) {
-    addr = Reg[base].u;
-    trace(Callstack_depth+1, "run") << "effective address is initially 0x" << HEXWORD << addr << " (" << rname(base) << ")" << end();
-  }
-  else {
-    // base == EBP && mod == 0
-    addr = next32();  // ignore base
-    trace(Callstack_depth+1, "run") << "effective address is initially 0x" << HEXWORD << addr << " (disp32)" << end();
-  }
-  const uint8_t index = (sib>>3)&0x7;
-  if (index == ESP) {
-    // ignore index and scale
-    trace(Callstack_depth+1, "run") << "effective address is 0x" << HEXWORD << addr << end();
-  }
-  else {
-    const uint8_t scale = (1 << (sib>>6));
-    addr += Reg[index].i*scale;  // treat index register as signed. Maybe base as well? But we'll always ensure it's non-negative.
-    trace(Callstack_depth+1, "run") << "effective address is 0x" << HEXWORD << addr << " (after adding " << rname(index) << "*" << NUM(scale) << ")" << end();
-  }
-  return addr;
-}
-
-:(code)
-void test_add_r32_to_mem_at_base_r32_index_r32() {
-  Reg[EBX].i = 0x10;  // source
-  Reg[EAX].i = 0x1ffe;  // dest base
-  Reg[ECX].i = 0x2;  // dest index
-  run(
-      "== code 0x1\n"
-      // op     ModR/M  SIB   displacement  immediate
-      "  01     1c      08                              \n"  // add EBX to *(EAX+ECX)
-      // ModR/M in binary: 00 (indirect mode) 011 (src EBX) 100 (dest in SIB)
-      // SIB in binary: 00 (scale 1) 001 (index ECX) 000 (base EAX)
-      "== data 0x2000\n"
-      "01 00 00 00\n"  // 1
-  );
-  CHECK_TRACE_CONTENTS(
-      "run: add EBX to r/m32\n"
-      "run: effective address is initially 0x00001ffe (EAX)\n"
-      "run: effective address is 0x00002000 (after adding ECX*1)\n"
-      "run: storing 0x00000011\n"
-  );
-}
-
-:(code)
-void test_add_r32_to_mem_at_displacement_using_sib() {
-  Reg[EBX].i = 0x10;  // source
-  run(
-      "== code 0x1\n"
-      // op     ModR/M  SIB   displacement  immediate
-      "  01     1c      25    00 20 00 00               \n"  // add EBX to *0x2000
-      // ModR/M in binary: 00 (indirect mode) 011 (src EBX) 100 (dest in SIB)
-      // SIB in binary: 00 (scale 1) 100 (no index) 101 (not EBP but disp32)
-      "== data 0x2000\n"
-      "01 00 00 00\n"  // 1
-  );
-  CHECK_TRACE_CONTENTS(
-      "run: add EBX to r/m32\n"
-      "run: effective address is initially 0x00002000 (disp32)\n"
-      "run: effective address is 0x00002000\n"
-      "run: storing 0x00000011\n"
-  );
-}
-
-//:
-
-:(code)
-void test_add_r32_to_mem_at_base_r32_index_r32_plus_disp8() {
-  Reg[EBX].i = 0x10;  // source
-  Reg[EAX].i = 0x1ff9;  // dest base
-  Reg[ECX].i = 0x5;  // dest index
-  run(
-      "== code 0x1\n"
-      // op     ModR/M  SIB   displacement  immediate
-      "  01     5c      08    02                        \n"  // add EBX to *(EAX+ECX+2)
-      // ModR/M in binary: 01 (indirect+disp8 mode) 011 (src EBX) 100 (dest in SIB)
-      // SIB in binary: 00 (scale 1) 001 (index ECX) 000 (base EAX)
-      "== data 0x2000\n"
-      "01 00 00 00\n"  // 1
-  );
-  CHECK_TRACE_CONTENTS(
-      "run: add EBX to r/m32\n"
-      "run: effective address is initially 0x00001ff9 (EAX)\n"
-      "run: effective address is 0x00001ffe (after adding ECX*1)\n"
-      "run: effective address is 0x00002000 (after adding disp8)\n"
-      "run: storing 0x00000011\n"
-  );
-}
-
-:(before "End Mod 1 Special-cases(addr)")
-case 4:  // exception: mod 0b01 rm 0b100 => incoming SIB (scale-index-base) byte
-  addr = effective_address_from_sib(mod);
-  break;
-
-//:
-
-:(code)
-void test_add_r32_to_mem_at_base_r32_index_r32_plus_disp32() {
-  Reg[EBX].i = 0x10;  // source
-  Reg[EAX].i = 0x1ff9;  // dest base
-  Reg[ECX].i = 0x5;  // dest index
-  run(
-      "== code 0x1\n"
-      // op     ModR/M  SIB   displacement  immediate
-      "  01     9c      08    02 00 00 00               \n"  // add EBX to *(EAX+ECX+2)
-      // ModR/M in binary: 10 (indirect+disp32 mode) 011 (src EBX) 100 (dest in SIB)
-      // SIB in binary: 00 (scale 1) 001 (index ECX) 000 (base EAX)
-      "== data 0x2000\n"
-      "01 00 00 00\n"  // 1
-  );
-  CHECK_TRACE_CONTENTS(
-      "run: add EBX to r/m32\n"
-      "run: effective address is initially 0x00001ff9 (EAX)\n"
-      "run: effective address is 0x00001ffe (after adding ECX*1)\n"
-      "run: effective address is 0x00002000 (after adding disp32)\n"
-      "run: storing 0x00000011\n"
-  );
-}
-
-:(before "End Mod 2 Special-cases(addr)")
-case 4:  // exception: mod 0b10 rm 0b100 => incoming SIB (scale-index-base) byte
-  addr = effective_address_from_sib(mod);
-  break;