4339

4 files changed, 101 insertions, 101 deletions

diff --git a/subx/011direct_addressing.cc b/subx/011direct_addressing.cc
index cf61fb82..66dbc43a 100644
--- a/subx/011direct_addressing.cc
+++ b/subx/011direct_addressing.cc
@@ -1,8 +1,8 @@
 //: operating directly on a register
 
 :(scenario add_r32_to_r32)
-% Reg[0].i = 0x10;
-% Reg[3].i = 1;
+% Reg[EAX].i = 0x10;
+% Reg[EBX].i = 1;
 # op  ModR/M  SIB   displacement  immediate
   01  d8                                      # add EBX to EAX
 # ModR/M in binary: 11 (direct mode) 011 (src EBX) 000 (dest EAX)
@@ -46,8 +46,8 @@ int32_t* effective_address(uint8_t modrm) {
 //:: subtract
 
 :(scenario subtract_r32_from_r32)
-% Reg[0].i = 10;
-% Reg[3].i = 1;
+% Reg[EAX].i = 10;
+% Reg[EBX].i = 1;
 # op  ModR/M  SIB   displacement  immediate
   29  d8                                      # subtract EBX from EAX
 # ModR/M in binary: 11 (direct mode) 011 (src EBX) 000 (dest EAX)
@@ -68,8 +68,8 @@ case 0x29: {  // subtract r32 from r/m32
 //:: and
 
 :(scenario and_r32_with_r32)
-% Reg[0].i = 0x0a0b0c0d;
-% Reg[3].i = 0x000000ff;
+% Reg[EAX].i = 0x0a0b0c0d;
+% Reg[EBX].i = 0x000000ff;
 # op  ModR/M  SIB   displacement  immediate
   21  d8                                      # and EBX with destination EAX
 # ModR/M in binary: 11 (direct mode) 011 (src EBX) 000 (dest EAX)
@@ -90,8 +90,8 @@ case 0x21: {  // and r32 with r/m32
 //:: or
 
 :(scenario or_r32_with_r32)
-% Reg[0].i = 0x0a0b0c0d;
-% Reg[3].i = 0xa0b0c0d0;
+% Reg[EAX].i = 0x0a0b0c0d;
+% Reg[EBX].i = 0xa0b0c0d0;
 # op  ModR/M  SIB   displacement  immediate
   09  d8                                      # or EBX with destination EAX
 # ModR/M in binary: 11 (direct mode) 011 (src EBX) 000 (dest EAX)
@@ -112,8 +112,8 @@ case 0x09: {  // or r32 with r/m32
 //:: xor
 
 :(scenario xor_r32_with_r32)
-% Reg[0].i = 0x0a0b0c0d;
-% Reg[3].i = 0xaabbc0d0;
+% Reg[EAX].i = 0x0a0b0c0d;
+% Reg[EBX].i = 0xaabbc0d0;
 # op  ModR/M  SIB   displacement  immediate
   31  d8                                      # xor EBX with destination EAX
 # ModR/M in binary: 11 (direct mode) 011 (src EBX) 000 (dest EAX)
@@ -134,7 +134,7 @@ case 0x31: {  // xor r32 with r/m32
 //:: not
 
 :(scenario not_r32)
-% Reg[3].i = 0x0f0f00ff;
+% Reg[EBX].i = 0x0f0f00ff;
 # op  ModR/M  SIB   displacement  immediate
   f7  c3                                      # not EBX
 # ModR/M in binary: 11 (direct mode) 000 (unused) 011 (dest EBX)
@@ -158,8 +158,8 @@ case 0xf7: {  // xor r32 with r/m32
 //:: compare (cmp)
 
 :(scenario compare_r32_with_r32_greater)
-% Reg[0].i = 0x0a0b0c0d;
-% Reg[3].i = 0x0a0b0c07;
+% Reg[EAX].i = 0x0a0b0c0d;
+% Reg[EBX].i = 0x0a0b0c07;
 # op  ModR/M  SIB   displacement  immediate
   39  d8                                      # compare EBX with EAX
 # ModR/M in binary: 11 (direct mode) 011 (src EBX) 000 (dest EAX)
@@ -184,8 +184,8 @@ case 0x39: {  // set SF if r/m32 < r32
 }
 
 :(scenario compare_r32_with_r32_lesser)
-% Reg[0].i = 0x0a0b0c07;
-% Reg[3].i = 0x0a0b0c0d;
+% Reg[EAX].i = 0x0a0b0c07;
+% Reg[EBX].i = 0x0a0b0c0d;
 # op  ModR/M  SIB   displacement  immediate
   39  d8                                      # compare EBX with EAX
 # ModR/M in binary: 11 (direct mode) 011 (src EBX) 000 (dest EAX)
@@ -194,8 +194,8 @@ case 0x39: {  // set SF if r/m32 < r32
 +run: SF=1; ZF=0; OF=0
 
 :(scenario compare_r32_with_r32_equal)
-% Reg[0].i = 0x0a0b0c0d;
-% Reg[3].i = 0x0a0b0c0d;
+% Reg[EAX].i = 0x0a0b0c0d;
+% Reg[EBX].i = 0x0a0b0c0d;
 # op  ModR/M  SIB   displacement  immediate
   39  d8                                      # compare EBX with EAX
 # ModR/M in binary: 11 (direct mode) 011 (src EBX) 000 (dest EAX)
@@ -206,7 +206,7 @@ case 0x39: {  // set SF if r/m32 < r32
 //:: copy (mov)
 
 :(scenario copy_r32_to_r32)
-% Reg[3].i = 0xaf;
+% Reg[EBX].i = 0xaf;
 # op  ModR/M  SIB   displacement  immediate
   89  d8                                      # copy EBX to EAX
 # ModR/M in binary: 11 (direct mode) 011 (src EBX) 000 (dest EAX)
@@ -228,8 +228,8 @@ case 0x89: {  // copy r32 to r/m32
 //:: xchg
 
 :(scenario xchg_r32_with_r32)
-% Reg[3].i = 0xaf;
-% Reg[0].i = 0x2e;
+% Reg[EBX].i = 0xaf;
+% Reg[EAX].i = 0x2e;
 # op  ModR/M  SIB   displacement  immediate
   87  d8                                      # exchange EBX with EAX
 # ModR/M in binary: 11 (direct mode) 011 (src EBX) 000 (dest EAX)
diff --git a/subx/012indirect_addressing.cc b/subx/012indirect_addressing.cc
index 304467f7..59147c2d 100644
--- a/subx/012indirect_addressing.cc
+++ b/subx/012indirect_addressing.cc
@@ -2,8 +2,8 @@
 //: we'll now start providing data in a separate segment
 
 :(scenario add_r32_to_mem_at_r32)
-% Reg[3].i = 0x10;
-% Reg[0].i = 0x60;
+% Reg[EBX].i = 0x10;
+% Reg[EAX].i = 0x60;
 == 0x01  # code segment
 # op  ModR/M  SIB   displacement  immediate
   01  18                                     # add EBX to *EAX
@@ -28,8 +28,8 @@ case 0:  // indirect addressing
 //:
 
 :(scenario add_mem_at_r32_to_r32)
-% Reg[0].i = 0x60;
-% Reg[3].i = 0x10;
+% Reg[EAX].i = 0x60;
+% Reg[EBX].i = 0x10;
 % write_mem_i32(0x60, 1);
 # op  ModR/M  SIB   displacement  immediate
   03  18                                      # add *EAX to EBX
@@ -51,9 +51,9 @@ case 0x03: {  // add r/m32 to r32
 //:: subtract
 
 :(scenario subtract_r32_from_mem_at_r32)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 10);
-% Reg[3].i = 1;
+% Reg[EBX].i = 1;
 # op  ModR/M  SIB   displacement  immediate
   29  18                                      # subtract EBX from *EAX
 # ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX)
@@ -64,9 +64,9 @@ case 0x03: {  // add r/m32 to r32
 //:
 
 :(scenario subtract_mem_at_r32_from_r32)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 1);
-% Reg[3].i = 10;
+% Reg[EBX].i = 10;
 # op  ModR/M  SIB   displacement  immediate
   2b  18                                      # subtract *EAX from EBX
 # ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX)
@@ -87,9 +87,9 @@ case 0x2b: {  // subtract r/m32 from r32
 //:: and
 
 :(scenario and_r32_with_mem_at_r32)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 0x0a0b0c0d);
-% Reg[3].i = 0xff;
+% Reg[EBX].i = 0xff;
 # op  ModR/M  SIB   displacement  immediate
   21  18                                      # and EBX with *EAX
 # ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX)
@@ -100,9 +100,9 @@ case 0x2b: {  // subtract r/m32 from r32
 //:
 
 :(scenario and_mem_at_r32_with_r32)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 0x000000ff);
-% Reg[3].i = 0x0a0b0c0d;
+% Reg[EBX].i = 0x0a0b0c0d;
 # op  ModR/M  SIB   displacement  immediate
   23  18                                      # and *EAX with EBX
 # ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX)
@@ -123,9 +123,9 @@ case 0x23: {  // and r/m32 with r32
 //:: or
 
 :(scenario or_r32_with_mem_at_r32)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 0x0a0b0c0d);
-% Reg[3].i = 0xa0b0c0d0;
+% Reg[EBX].i = 0xa0b0c0d0;
 # op  ModR/M  SIB   displacement  immediate
   09  18                                      # or EBX with *EAX
 # ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX)
@@ -136,9 +136,9 @@ case 0x23: {  // and r/m32 with r32
 //:
 
 :(scenario or_mem_at_r32_with_r32)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 0x0a0b0c0d);
-% Reg[3].i = 0xa0b0c0d0;
+% Reg[EBX].i = 0xa0b0c0d0;
 # op  ModR/M  SIB   displacement  immediate
   0b  18                                      # or *EAX with EBX
 # ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX)
@@ -159,9 +159,9 @@ case 0x0b: {  // or r/m32 with r32
 //:: xor
 
 :(scenario xor_r32_with_mem_at_r32)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 0xaabb0c0d);
-% Reg[3].i = 0xa0b0c0d0;
+% Reg[EBX].i = 0xa0b0c0d0;
 # op  ModR/M  SIB   displacement  immediate
   31  18                                      # xor EBX with *EAX
 # ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX)
@@ -172,9 +172,9 @@ case 0x0b: {  // or r/m32 with r32
 //:
 
 :(scenario xor_mem_at_r32_with_r32)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 0x0a0b0c0d);
-% Reg[3].i = 0xa0b0c0d0;
+% Reg[EBX].i = 0xa0b0c0d0;
 # op  ModR/M  SIB   displacement  immediate
   33  18                                      # xor *EAX with EBX
 # ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX)
@@ -195,7 +195,7 @@ case 0x33: {  // xor r/m32 with r32
 //:: not
 
 :(scenario not_r32_with_mem_at_r32)
-% Reg[3].i = 0x60;
+% Reg[EBX].i = 0x60;
 # word at 0x60 is 0x0f0f00ff
 % write_mem_i32(0x60, 0x0f0f00ff);
 # op  ModR/M  SIB   displacement  immediate
@@ -208,9 +208,9 @@ case 0x33: {  // xor r/m32 with r32
 //:: compare (cmp)
 
 :(scenario compare_mem_at_r32_with_r32_greater)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 0x0a0b0c0d);
-% Reg[3].i = 0x0a0b0c07;
+% Reg[EBX].i = 0x0a0b0c07;
 # op  ModR/M  SIB   displacement  immediate
   39  18                                      # compare EBX with *EAX
 # ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX)
@@ -219,9 +219,9 @@ case 0x33: {  // xor r/m32 with r32
 +run: SF=0; ZF=0; OF=0
 
 :(scenario compare_mem_at_r32_with_r32_lesser)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 0x0a0b0c07);
-% Reg[3].i = 0x0a0b0c0d;
+% Reg[EBX].i = 0x0a0b0c0d;
 # op  ModR/M  SIB   displacement  immediate
   39  18                                      # compare EBX with *EAX
 # ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX)
@@ -230,9 +230,9 @@ case 0x33: {  // xor r/m32 with r32
 +run: SF=1; ZF=0; OF=0
 
 :(scenario compare_mem_at_r32_with_r32_equal)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 0x0a0b0c0d);
-% Reg[3].i = 0x0a0b0c0d;
+% Reg[EBX].i = 0x0a0b0c0d;
 # op  ModR/M  SIB   displacement  immediate
   39  18                                      # compare EBX with *EAX
 # ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX)
@@ -243,9 +243,9 @@ case 0x33: {  // xor r/m32 with r32
 //:
 
 :(scenario compare_r32_with_mem_at_r32_greater)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 0x0a0b0c07);
-% Reg[3].i = 0x0a0b0c0d;
+% Reg[EBX].i = 0x0a0b0c0d;
 # op  ModR/M  SIB   displacement  immediate
   3b  18                                      # compare *EAX with EBX
 # ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX)
@@ -270,9 +270,9 @@ case 0x3b: {  // set SF if r32 < r/m32
 }
 
 :(scenario compare_r32_with_mem_at_r32_lesser)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 0x0a0b0c0d);
-% Reg[3].i = 0x0a0b0c07;
+% Reg[EBX].i = 0x0a0b0c07;
 # op  ModR/M  SIB   displacement  immediate
   3b  18                                      # compare *EAX with EBX
 # ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX)
@@ -281,9 +281,9 @@ case 0x3b: {  // set SF if r32 < r/m32
 +run: SF=1; ZF=0; OF=0
 
 :(scenario compare_r32_with_mem_at_r32_equal)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 0x0a0b0c0d);
-% Reg[3].i = 0x0a0b0c0d;
+% Reg[EBX].i = 0x0a0b0c0d;
 # op  ModR/M  SIB   displacement  immediate
   3b  18                                      # compare *EAX with EBX
 # ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX)
@@ -294,8 +294,8 @@ case 0x3b: {  // set SF if r32 < r/m32
 //:: copy (mov)
 
 :(scenario copy_r32_to_mem_at_r32)
-% Reg[3].i = 0xaf;
-% Reg[0].i = 0x60;
+% Reg[EBX].i = 0xaf;
+% Reg[EAX].i = 0x60;
 # op  ModR/M  SIB   displacement  immediate
   89  18                                      # copy EBX to *EAX
 # ModR/M in binary: 00 (indirect mode) 011 (src EAX) 000 (dest EAX)
@@ -306,7 +306,7 @@ case 0x3b: {  // set SF if r32 < r/m32
 //:
 
 :(scenario copy_mem_at_r32_to_r32)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 0x000000af);
 # op  ModR/M  SIB   displacement  immediate
   8b  18                                      # copy *EAX to EBX
@@ -329,7 +329,7 @@ case 0x8b: {  // copy r32 to r/m32
 //:: jump
 
 :(scenario jump_mem_at_r32)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 8);
 # op  ModR/M  SIB   displacement  immediate
   ff  20                                      # jump to *EAX
@@ -363,7 +363,7 @@ case 0xff: {
 //:: push
 
 :(scenario push_mem_at_r32)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 0x000000af);
 % Reg[ESP].u = 0x14;
 # op  ModR/M  SIB   displacement  immediate
@@ -385,7 +385,7 @@ case 6: {  // push r/m32 to stack
 //:: pop
 
 :(scenario pop_mem_at_r32)
-% Reg[0].i = 0x60;
+% Reg[EAX].i = 0x60;
 % Reg[ESP].u = 0x10;
 % write_mem_i32(0x10, 0x00000030);
 # op  ModR/M  SIB   displacement  immediate
@@ -414,7 +414,7 @@ case 0x8f: {  // pop stack into r/m32
 //:: special-case for loading address from disp32 rather than register
 
 :(scenario add_r32_to_mem_at_displacement)
-% Reg[3].i = 0x10;  // source
+% Reg[EBX].i = 0x10;  // source
 % write_mem_i32(0x60, 1);
 # op  ModR/M  SIB   displacement  immediate
   01  1d            60 00 00 00              # add EBX to *0x60
@@ -432,8 +432,8 @@ case 5:  // exception: mod 0b00 rm 0b101 => incoming disp32
 //:
 
 :(scenario add_r32_to_mem_at_r32_plus_disp8)
-% Reg[3].i = 0x10;  // source
-% Reg[0].i = 0x5e;  // dest
+% Reg[EBX].i = 0x10;  // source
+% Reg[EAX].i = 0x5e;  // dest
 % write_mem_i32(0x60, 1);
 # op  ModR/M  SIB   displacement  immediate
   01  58            02                       # add EBX to *(EAX+2)
@@ -459,8 +459,8 @@ case 1:  // indirect + disp8 addressing
   break;
 
 :(scenario add_r32_to_mem_at_r32_plus_negative_disp8)
-% Reg[3].i = 0x10;  // source
-% Reg[0].i = 0x61;  // dest
+% Reg[EBX].i = 0x10;  // source
+% Reg[EAX].i = 0x61;  // dest
 % write_mem_i32(0x60, 1);
 # op  ModR/M  SIB   displacement  immediate
   01  58            ff                       # add EBX to *(EAX-1)
@@ -473,8 +473,8 @@ case 1:  // indirect + disp8 addressing
 //:
 
 :(scenario add_r32_to_mem_at_r32_plus_disp32)
-% Reg[3].i = 0x10;  // source
-% Reg[0].i = 0x5e;  // dest
+% Reg[EBX].i = 0x10;  // source
+% Reg[EAX].i = 0x5e;  // dest
 % write_mem_i32(0x60, 1);
 # op  ModR/M  SIB   displacement  immediate
   01  98            02 00 00 00              # add EBX to *(EAX+2)
@@ -500,8 +500,8 @@ case 2:  // indirect + disp32 addressing
   break;
 
 :(scenario add_r32_to_mem_at_r32_plus_negative_disp32)
-% Reg[3].i = 0x10;  // source
-% Reg[0].i = 0x61;  // dest
+% Reg[EBX].i = 0x10;  // source
+% Reg[EAX].i = 0x61;  // dest
 % write_mem_i32(0x60, 1);
 # op  ModR/M  SIB   displacement  immediate
   01  98            ff ff ff ff              # add EBX to *(EAX-1)
diff --git a/subx/013immediate_addressing.cc b/subx/013immediate_addressing.cc
index 78510535..ceb998ef 100644
--- a/subx/013immediate_addressing.cc
+++ b/subx/013immediate_addressing.cc
@@ -1,7 +1,7 @@
 //: instructions that (immediately) contain an argument to act with
 
 :(scenario add_imm32_to_r32)
-% Reg[3].i = 1;
+% Reg[EBX].i = 1;
 # op  ModR/M  SIB   displacement  immediate
   81  c3                          0a 0b 0c 0d  # add 0x0d0c0b0a to EBX
 # ModR/M in binary: 11 (direct mode) 000 (add imm32) 011 (dest EBX)
@@ -33,7 +33,7 @@ case 0x81: {  // combine imm32 with r/m32
 //:
 
 :(scenario add_imm32_to_mem_at_r32)
-% Reg[3].i = 0x60;
+% Reg[EBX].i = 0x60;
 % write_mem_i32(0x60, 1);
 # op  ModR/M  SIB   displacement  immediate
   81  03                          0a 0b 0c 0d  # add 0x0d0c0b0a to *EBX
@@ -63,7 +63,7 @@ case 0x2d: {  // subtract imm32 from EAX
 //:
 
 :(scenario subtract_imm32_from_mem_at_r32)
-% Reg[3].i = 0x60;
+% Reg[EBX].i = 0x60;
 % write_mem_i32(0x60, 10);
 # op  ModR/M  SIB   displacement  immediate
   81  2b                          01 00 00 00  # subtract 1 from *EBX
@@ -83,7 +83,7 @@ case 5: {
 //:
 
 :(scenario subtract_imm32_from_r32)
-% Reg[3].i = 10;
+% Reg[EBX].i = 10;
 # op  ModR/M  SIB   displacement  immediate
   81  eb                          01 00 00 00  # subtract 1 from EBX
 # ModR/M in binary: 11 (direct mode) 101 (subtract imm32) 011 (dest EBX)
@@ -112,7 +112,7 @@ case 0x25: {  // and imm32 with EAX
 //:
 
 :(scenario and_imm32_with_mem_at_r32)
-% Reg[3].i = 0x60;
+% Reg[EBX].i = 0x60;
 % write_mem_i32(0x60, 0x000000ff);
 # op  ModR/M  SIB   displacement  immediate
   81  23                          0a 0b 0c 0d  # and 0x0d0c0b0a with *EBX
@@ -132,7 +132,7 @@ case 4: {
 //:
 
 :(scenario and_imm32_with_r32)
-% Reg[3].i = 0xff;
+% Reg[EBX].i = 0xff;
 # op  ModR/M  SIB   displacement  immediate
   81  e3                          0a 0b 0c 0d  # and 0x0d0c0b0a with EBX
 # ModR/M in binary: 11 (direct mode) 100 (and imm32) 011 (dest EBX)
@@ -161,7 +161,7 @@ case 0x0d: {  // or imm32 with EAX
 //:
 
 :(scenario or_imm32_with_mem_at_r32)
-% Reg[3].i = 0x60;
+% Reg[EBX].i = 0x60;
 % write_mem_i32(0x60, 0xd0c0b0a0);
 # op  ModR/M  SIB   displacement  immediate
   81  0b                          0a 0b 0c 0d  # or 0x0d0c0b0a with *EBX
@@ -179,7 +179,7 @@ case 1: {
 }
 
 :(scenario or_imm32_with_r32)
-% Reg[3].i = 0xd0c0b0a0;
+% Reg[EBX].i = 0xd0c0b0a0;
 # op  ModR/M  SIB   displacement  immediate
   81  cb                          0a 0b 0c 0d  # or 0x0d0c0b0a with EBX
 # ModR/M in binary: 11 (direct mode) 001 (or imm32) 011 (dest EBX)
@@ -208,7 +208,7 @@ case 0x35: {  // xor imm32 with EAX
 //:
 
 :(scenario xor_imm32_with_mem_at_r32)
-% Reg[3].i = 0x60;
+% Reg[EBX].i = 0x60;
 % write_mem_i32(0x60, 0xd0c0b0a0);
 # op  ModR/M  SIB   displacement  immediate
   81  33                          0a 0b 0c 0d  # xor 0x0d0c0b0a with *EBX
@@ -226,7 +226,7 @@ case 6: {
 }
 
 :(scenario xor_imm32_with_r32)
-% Reg[3].i = 0xd0c0b0a0;
+% Reg[EBX].i = 0xd0c0b0a0;
 # op  ModR/M  SIB   displacement  immediate
   81  f3                          0a 0b 0c 0d  # xor 0x0d0c0b0a with EBX
 # ModR/M in binary: 11 (direct mode) 110 (xor imm32) 011 (dest EBX)
@@ -238,7 +238,7 @@ case 6: {
 //:: compare (cmp)
 
 :(scenario compare_imm32_with_eax_greater)
-% Reg[0].i = 0x0d0c0b0a;
+% Reg[EAX].i = 0x0d0c0b0a;
 # op  ModR/M  SIB   displacement  immediate
   3d                              07 0b 0c 0d  # compare 0x0d0c0b07 with EAX
 +run: compare EAX and imm32 0x0d0c0b07
@@ -259,14 +259,14 @@ case 0x3d: {  // subtract imm32 from EAX
 }
 
 :(scenario compare_imm32_with_eax_lesser)
-% Reg[0].i = 0x0d0c0b07;
+% Reg[EAX].i = 0x0d0c0b07;
 # op  ModR/M  SIB   displacement  immediate
   3d                              0a 0b 0c 0d  # compare 0x0d0c0b0a with EAX
 +run: compare EAX and imm32 0x0d0c0b0a
 +run: SF=1; ZF=0; OF=0
 
 :(scenario compare_imm32_with_eax_equal)
-% Reg[0].i = 0x0d0c0b0a;
+% Reg[EAX].i = 0x0d0c0b0a;
 # op  ModR/M  SIB   displacement  immediate
   3d                              0a 0b 0c 0d  # compare 0x0d0c0b0a with EAX
 +run: compare EAX and imm32 0x0d0c0b0a
@@ -275,7 +275,7 @@ case 0x3d: {  // subtract imm32 from EAX
 //:
 
 :(scenario compare_imm32_with_r32_greater)
-% Reg[3].i = 0x0d0c0b0a;
+% Reg[EBX].i = 0x0d0c0b0a;
 # op  ModR/M  SIB   displacement  immediate
   81  fb                          07 0b 0c 0d  # compare 0x0d0c0b07 with EBX
 # ModR/M in binary: 11 (direct mode) 111 (compare imm32) 011 (dest EBX)
@@ -296,7 +296,7 @@ case 7: {
 }
 
 :(scenario compare_imm32_with_r32_lesser)
-% Reg[3].i = 0x0d0c0b07;
+% Reg[EBX].i = 0x0d0c0b07;
 # op  ModR/M  SIB   displacement  immediate
   81  fb                          0a 0b 0c 0d  # compare 0x0d0c0b0a with EBX
 # ModR/M in binary: 11 (direct mode) 111 (compare imm32) 011 (dest EBX)
@@ -305,7 +305,7 @@ case 7: {
 +run: SF=1; ZF=0; OF=0
 
 :(scenario compare_imm32_with_r32_equal)
-% Reg[3].i = 0x0d0c0b0a;
+% Reg[EBX].i = 0x0d0c0b0a;
 # op  ModR/M  SIB   displacement  immediate
   81  fb                          0a 0b 0c 0d  # compare 0x0d0c0b0a with EBX
 # ModR/M in binary: 11 (direct mode) 111 (compare imm32) 011 (dest EBX)
@@ -314,7 +314,7 @@ case 7: {
 +run: SF=0; ZF=1; OF=0
 
 :(scenario compare_imm32_with_mem_at_r32_greater)
-% Reg[3].i = 0x60;
+% Reg[EBX].i = 0x60;
 % write_mem_i32(0x60, 0x0d0c0b0a);
 # op  ModR/M  SIB   displacement  immediate
   81  3b                          07 0b 0c 0d  # compare 0x0d0c0b07 with *EBX
@@ -324,7 +324,7 @@ case 7: {
 +run: SF=0; ZF=0; OF=0
 
 :(scenario compare_imm32_with_mem_at_r32_lesser)
-% Reg[3].i = 0x60;
+% Reg[EBX].i = 0x60;
 % write_mem_i32(0x60, 0x0d0c0b07);
 # op  ModR/M  SIB   displacement  immediate
   81  3b                          0a 0b 0c 0d  # compare 0x0d0c0b0a with *EBX
@@ -334,8 +334,8 @@ case 7: {
 +run: SF=1; ZF=0; OF=0
 
 :(scenario compare_imm32_with_mem_at_r32_equal)
-% Reg[3].i = 0x0d0c0b0a;
-% Reg[3].i = 0x60;
+% Reg[EBX].i = 0x0d0c0b0a;
+% Reg[EBX].i = 0x60;
 % write_mem_i32(0x60, 0x0d0c0b0a);
 # op  ModR/M  SIB   displacement  immediate
   81  3b                          0a 0b 0c 0d  # compare 0x0d0c0b0a with *EBX
@@ -370,7 +370,7 @@ case 0xbf: {  // copy imm32 to r32
 //:
 
 :(scenario copy_imm32_to_mem_at_r32)
-% Reg[3].i = 0x60;
+% Reg[EBX].i = 0x60;
 # op  ModR/M  SIB   displacement  immediate
   c7  03                          0a 0b 0c 0d  # copy 0x0d0c0b0a to *EBX
 # ModR/M in binary: 00 (indirect mode) 000 (unused) 011 (dest EBX)
diff --git a/subx/014index_addressing.cc b/subx/014index_addressing.cc
index 6b07436f..fe80de13 100644
--- a/subx/014index_addressing.cc
+++ b/subx/014index_addressing.cc
@@ -1,8 +1,8 @@
 //: operating on memory at the address provided by some register plus optional scale and offset
 
 :(scenario add_r32_to_mem_at_r32_with_sib)
-% Reg[3].i = 0x10;
-% Reg[0].i = 0x60;
+% Reg[EBX].i = 0x10;
+% Reg[EAX].i = 0x60;
 % write_mem_i32(0x60, 1);
 # op  ModR/M  SIB   displacement  immediate
   01  1c      20                             # add EBX to *EAX
@@ -45,9 +45,9 @@ uint32_t effective_address_from_sib(uint8_t mod) {
 }
 
 :(scenario add_r32_to_mem_at_base_r32_index_r32)
-% Reg[3].i = 0x10;  // source
-% Reg[0].i = 0x5e;  // dest base
-% Reg[1].i = 0x2;  // dest index
+% Reg[EBX].i = 0x10;  // source
+% Reg[EAX].i = 0x5e;  // dest base
+% Reg[ECX].i = 0x2;  // dest index
 % write_mem_i32(0x60, 1);
 # op  ModR/M  SIB   displacement  immediate
   01  1c      08                             # add EBX to *(EAX+ECX)
@@ -59,7 +59,7 @@ uint32_t effective_address_from_sib(uint8_t mod) {
 +run: storing 0x00000011
 
 :(scenario add_r32_to_mem_at_displacement_using_sib)
-% Reg[3].i = 0x10;  // source
+% Reg[EBX].i = 0x10;  // source
 % write_mem_i32(0x60, 1);
 # op  ModR/M  SIB   displacement  immediate
   01  1c      25    60 00 00 00              # add EBX to *0x60
@@ -73,9 +73,9 @@ uint32_t effective_address_from_sib(uint8_t mod) {
 //:
 
 :(scenario add_r32_to_mem_at_base_r32_index_r32_plus_disp8)
-% Reg[3].i = 0x10;  // source
-% Reg[0].i = 0x59;  // dest base
-% Reg[1].i = 0x5;  // dest index
+% Reg[EBX].i = 0x10;  // source
+% Reg[EAX].i = 0x59;  // dest base
+% Reg[ECX].i = 0x5;  // dest index
 % write_mem_i32(0x60, 1);
 # op  ModR/M  SIB   displacement  immediate
   01  5c      08    02                       # add EBX to *(EAX+ECX+2)
@@ -95,9 +95,9 @@ case 4:  // exception: mod 0b01 rm 0b100 => incoming SIB (scale-index-base) byte
 //:
 
 :(scenario add_r32_to_mem_at_base_r32_index_r32_plus_disp32)
-% Reg[3].i = 0x10;  // source
-% Reg[0].i = 0x59;  // dest base
-% Reg[1].i = 0x5;  // dest index
+% Reg[EBX].i = 0x10;  // source
+% Reg[EAX].i = 0x59;  // dest base
+% Reg[ECX].i = 0x5;  // dest index
 % write_mem_i32(0x60, 1);
 # op  ModR/M  SIB   displacement  immediate
   01  9c      08    02 00 00 00              # add EBX to *(EAX+ECX+2)