diff options
Diffstat (limited to 'linux/bootstrap/022float.cc')
| -rw-r--r-- | linux/bootstrap/022float.cc | 519 |
1 files changed, 519 insertions, 0 deletions
diff --git a/linux/bootstrap/022float.cc b/linux/bootstrap/022float.cc new file mode 100644 index 00000000..7b313c25 --- /dev/null +++ b/linux/bootstrap/022float.cc @@ -0,0 +1,519 @@ +//: floating-point operations + +//:: copy + +:(before "End Initialize Op Names") +put_new(Name_f3_0f, "10", "copy xm32 to x32 (movss)"); +put_new(Name_f3_0f, "11", "copy x32 to xm32 (movss)"); + +:(code) +void test_copy_x32_to_x32() { + Xmm[3] = 0.5; + run( + "== code 0x1\n" // code segment + // op ModR/M SIB displacement immediate + "f3 0f 11 d8 \n" // copy XMM3 to XMM0 + // ModR/M in binary: 11 (direct mode) 011 (src XMM3) 000 (dest XMM0) + ); + CHECK_TRACE_CONTENTS( + "run: copy XMM3 to x/m32\n" + "run: x/m32 is XMM0\n" + "run: storing 0.5\n" + ); +} + +:(before "End Three-Byte Opcodes Starting With f3 0f") +case 0x10: { // copy x/m32 to x32 + const uint8_t modrm = next(); + const uint8_t rdest = (modrm>>3)&0x7; + trace(Callstack_depth+1, "run") << "copy x/m32 to " << Xname[rdest] << end(); + float* src = effective_address_float(modrm); + Xmm[rdest] = *src; // Write multiple elements of vector<uint8_t> at once. Assumes sizeof(float) == 4 on the host as well. + trace(Callstack_depth+1, "run") << "storing " << Xmm[rdest] << end(); + break; +} +case 0x11: { // copy x32 to x/m32 + const uint8_t modrm = next(); + const uint8_t rsrc = (modrm>>3)&0x7; + trace(Callstack_depth+1, "run") << "copy " << Xname[rsrc] << " to x/m32" << end(); + float* dest = effective_address_float(modrm); + *dest = Xmm[rsrc]; // Write multiple elements of vector<uint8_t> at once. Assumes sizeof(float) == 4 on the host as well. + trace(Callstack_depth+1, "run") << "storing " << *dest << end(); + break; +} + +:(code) +void test_copy_x32_to_mem_at_xm32() { + Xmm[3] = 0.5; + Reg[EAX].i = 0x60; + run( + "== code 0x1\n" + // op ModR/M SIB displacement immediate + "f3 0f 11 18 \n" // copy XMM3 to *EAX + // ModR/M in binary: 00 (indirect mode) 011 (src XMM3) 000 (dest EAX) + ); + CHECK_TRACE_CONTENTS( + "run: copy XMM3 to x/m32\n" + "run: effective address is 0x00000060 (EAX)\n" + "run: storing 0.5\n" + ); +} + +void test_copy_mem_at_xm32_to_x32() { + Reg[EAX].i = 0x2000; + run( + "== code 0x1\n" + // op ModR/M SIB displacement immediate + "f3 0f 10 18 \n" // copy *EAX to XMM3 + "== data 0x2000\n" + "00 00 00 3f\n" // 0x3f000000 = 0.5 + ); + CHECK_TRACE_CONTENTS( + "run: copy x/m32 to XMM3\n" + "run: effective address is 0x00002000 (EAX)\n" + "run: storing 0.5\n" + ); +} + +//:: convert to floating point + +:(before "End Initialize Op Names") +put_new(Name_f3_0f, "2a", "convert integer to floating-point (cvtsi2ss)"); + +:(code) +void test_cvtsi2ss() { + Reg[EAX].i = 10; + run( + "== code 0x1\n" + // op ModR/M SIB displacement immediate + "f3 0f 2a c0 \n" + // ModR/M in binary: 11 (direct mode) 000 (XMM0) 000 (EAX) + ); + CHECK_TRACE_CONTENTS( + "run: convert r/m32 to XMM0\n" + "run: r/m32 is EAX\n" + "run: XMM0 is now 10\n" + ); +} + +:(before "End Three-Byte Opcodes Starting With f3 0f") +case 0x2a: { // convert integer to float + const uint8_t modrm = next(); + const uint8_t dest = (modrm>>3)&0x7; + trace(Callstack_depth+1, "run") << "convert r/m32 to " << Xname[dest] << end(); + const int32_t* src = effective_address(modrm); + Xmm[dest] = *src; + trace(Callstack_depth+1, "run") << Xname[dest] << " is now " << Xmm[dest] << end(); + break; +} + +//:: convert floating point to int + +:(before "End Initialize Op Names") +put_new(Name_f3_0f, "2d", "convert floating-point to int (cvtss2si)"); +put_new(Name_f3_0f, "2c", "truncate floating-point to int (cvttss2si)"); + +:(code) +void test_cvtss2si() { + Xmm[0] = 9.8; + run( + "== code 0x1\n" + // op ModR/M SIB displacement immediate + "f3 0f 2d c0 \n" + // ModR/M in binary: 11 (direct mode) 000 (EAX) 000 (XMM0) + ); + CHECK_TRACE_CONTENTS( + "run: convert x/m32 to EAX\n" + "run: x/m32 is XMM0\n" + "run: EAX is now 0x0000000a\n" + ); +} + +:(before "End Three-Byte Opcodes Starting With f3 0f") +case 0x2d: { // convert float to integer + const uint8_t modrm = next(); + const uint8_t dest = (modrm>>3)&0x7; + trace(Callstack_depth+1, "run") << "convert x/m32 to " << rname(dest) << end(); + const float* src = effective_address_float(modrm); + Reg[dest].i = round(*src); + trace(Callstack_depth+1, "run") << rname(dest) << " is now 0x" << HEXWORD << Reg[dest].i << end(); + break; +} + +:(code) +void test_cvttss2si() { + Xmm[0] = 9.8; + run( + "== code 0x1\n" + // op ModR/M SIB displacement immediate + "f3 0f 2c c0 \n" + // ModR/M in binary: 11 (direct mode) 000 (EAX) 000 (XMM0) + ); + CHECK_TRACE_CONTENTS( + "run: truncate x/m32 to EAX\n" + "run: x/m32 is XMM0\n" + "run: EAX is now 0x00000009\n" + ); +} + +:(before "End Three-Byte Opcodes Starting With f3 0f") +case 0x2c: { // truncate float to integer + const uint8_t modrm = next(); + const uint8_t dest = (modrm>>3)&0x7; + trace(Callstack_depth+1, "run") << "truncate x/m32 to " << rname(dest) << end(); + const float* src = effective_address_float(modrm); + Reg[dest].i = trunc(*src); + trace(Callstack_depth+1, "run") << rname(dest) << " is now 0x" << HEXWORD << Reg[dest].i << end(); + break; +} + +//:: add + +:(before "End Initialize Op Names") +put_new(Name_f3_0f, "58", "add floats (addss)"); + +:(code) +void test_addss() { + Xmm[0] = 3.0; + Xmm[1] = 2.0; + run( + "== code 0x1\n" + // op ModR/M SIB displacement immediate + "f3 0f 58 c1 \n" + // ModR/M in binary: 11 (direct mode) 000 (XMM0) 001 (XMM1) + ); + CHECK_TRACE_CONTENTS( + "run: add x/m32 to XMM0\n" + "run: x/m32 is XMM1\n" + "run: XMM0 is now 5\n" + ); +} + +:(before "End Three-Byte Opcodes Starting With f3 0f") +case 0x58: { // add x/m32 to x32 + const uint8_t modrm = next(); + const uint8_t dest = (modrm>>3)&0x7; + trace(Callstack_depth+1, "run") << "add x/m32 to " << Xname[dest] << end(); + const float* src = effective_address_float(modrm); + Xmm[dest] += *src; + trace(Callstack_depth+1, "run") << Xname[dest] << " is now " << Xmm[dest] << end(); + break; +} + +//:: subtract + +:(before "End Initialize Op Names") +put_new(Name_f3_0f, "5c", "subtract floats (subss)"); + +:(code) +void test_subss() { + Xmm[0] = 3.0; + Xmm[1] = 2.0; + run( + "== code 0x1\n" + // op ModR/M SIB displacement immediate + "f3 0f 5c c1 \n" + // ModR/M in binary: 11 (direct mode) 000 (XMM0) 001 (XMM1) + ); + CHECK_TRACE_CONTENTS( + "run: subtract x/m32 from XMM0\n" + "run: x/m32 is XMM1\n" + "run: XMM0 is now 1\n" + ); +} + +:(before "End Three-Byte Opcodes Starting With f3 0f") +case 0x5c: { // subtract x/m32 from x32 + const uint8_t modrm = next(); + const uint8_t dest = (modrm>>3)&0x7; + trace(Callstack_depth+1, "run") << "subtract x/m32 from " << Xname[dest] << end(); + const float* src = effective_address_float(modrm); + Xmm[dest] -= *src; + trace(Callstack_depth+1, "run") << Xname[dest] << " is now " << Xmm[dest] << end(); + break; +} + +//:: multiply + +:(before "End Initialize Op Names") +put_new(Name_f3_0f, "59", "multiply floats (mulss)"); + +:(code) +void test_mulss() { + Xmm[0] = 3.0; + Xmm[1] = 2.0; + run( + "== code 0x1\n" + // op ModR/M SIB displacement immediate + "f3 0f 59 c1 \n" + // ModR/M in binary: 11 (direct mode) 000 (XMM0) 001 (XMM1) + ); + CHECK_TRACE_CONTENTS( + "run: multiply XMM0 by x/m32\n" + "run: x/m32 is XMM1\n" + "run: XMM0 is now 6\n" + ); +} + +:(before "End Three-Byte Opcodes Starting With f3 0f") +case 0x59: { // multiply x32 by x/m32 + const uint8_t modrm = next(); + const uint8_t dest = (modrm>>3)&0x7; + trace(Callstack_depth+1, "run") << "multiply " << Xname[dest] << " by x/m32" << end(); + const float* src = effective_address_float(modrm); + Xmm[dest] *= *src; + trace(Callstack_depth+1, "run") << Xname[dest] << " is now " << Xmm[dest] << end(); + break; +} + +//:: divide + +:(before "End Initialize Op Names") +put_new(Name_f3_0f, "5e", "divide floats (divss)"); + +:(code) +void test_divss() { + Xmm[0] = 3.0; + Xmm[1] = 2.0; + run( + "== code 0x1\n" + // op ModR/M SIB displacement immediate + "f3 0f 5e c1 \n" + // ModR/M in binary: 11 (direct mode) 000 (XMM0) 001 (XMM1) + ); + CHECK_TRACE_CONTENTS( + "run: divide XMM0 by x/m32\n" + "run: x/m32 is XMM1\n" + "run: XMM0 is now 1.5\n" + ); +} + +:(before "End Three-Byte Opcodes Starting With f3 0f") +case 0x5e: { // divide x32 by x/m32 + const uint8_t modrm = next(); + const uint8_t dest = (modrm>>3)&0x7; + trace(Callstack_depth+1, "run") << "divide " << Xname[dest] << " by x/m32" << end(); + const float* src = effective_address_float(modrm); + Xmm[dest] /= *src; + trace(Callstack_depth+1, "run") << Xname[dest] << " is now " << Xmm[dest] << end(); + break; +} + +//:: min + +:(before "End Initialize Op Names") +put_new(Name_f3_0f, "5d", "minimum of two floats (minss)"); + +:(code) +void test_minss() { + Xmm[0] = 3.0; + Xmm[1] = 2.0; + run( + "== code 0x1\n" + // op ModR/M SIB displacement immediate + "f3 0f 5d c1 \n" + // ModR/M in binary: 11 (direct mode) 000 (XMM0) 001 (XMM1) + ); + CHECK_TRACE_CONTENTS( + "run: minimum of XMM0 and x/m32\n" + "run: x/m32 is XMM1\n" + "run: XMM0 is now 2\n" + ); +} + +:(before "End Three-Byte Opcodes Starting With f3 0f") +case 0x5d: { // minimum of x32, x/m32 + const uint8_t modrm = next(); + const uint8_t dest = (modrm>>3)&0x7; + trace(Callstack_depth+1, "run") << "minimum of " << Xname[dest] << " and x/m32" << end(); + const float* src = effective_address_float(modrm); + Xmm[dest] = min(Xmm[dest], *src); + trace(Callstack_depth+1, "run") << Xname[dest] << " is now " << Xmm[dest] << end(); + break; +} + +//:: max + +:(before "End Initialize Op Names") +put_new(Name_f3_0f, "5f", "maximum of two floats (maxss)"); + +:(code) +void test_maxss() { + Xmm[0] = 3.0; + Xmm[1] = 2.0; + run( + "== code 0x1\n" + // op ModR/M SIB displacement immediate + "f3 0f 5f c1 \n" + // ModR/M in binary: 11 (direct mode) 000 (XMM0) 001 (XMM1) + ); + CHECK_TRACE_CONTENTS( + "run: maximum of XMM0 and x/m32\n" + "run: x/m32 is XMM1\n" + "run: XMM0 is now 3\n" + ); +} + +:(before "End Three-Byte Opcodes Starting With f3 0f") +case 0x5f: { // maximum of x32, x/m32 + const uint8_t modrm = next(); + const uint8_t dest = (modrm>>3)&0x7; + trace(Callstack_depth+1, "run") << "maximum of " << Xname[dest] << " and x/m32" << end(); + const float* src = effective_address_float(modrm); + Xmm[dest] = max(Xmm[dest], *src); + trace(Callstack_depth+1, "run") << Xname[dest] << " is now " << Xmm[dest] << end(); + break; +} + +//:: reciprocal + +:(before "End Initialize Op Names") +put_new(Name_f3_0f, "53", "reciprocal of float (rcpss)"); + +:(code) +void test_rcpss() { + Xmm[1] = 2.0; + run( + "== code 0x1\n" + // op ModR/M SIB displacement immediate + "f3 0f 53 c1 \n" + // ModR/M in binary: 11 (direct mode) 000 (XMM0) 001 (XMM1) + ); + CHECK_TRACE_CONTENTS( + "run: reciprocal of x/m32 into XMM0\n" + "run: x/m32 is XMM1\n" + "run: XMM0 is now 0.5\n" + ); +} + +:(before "End Three-Byte Opcodes Starting With f3 0f") +case 0x53: { // reciprocal of x/m32 into x32 + const uint8_t modrm = next(); + const uint8_t dest = (modrm>>3)&0x7; + trace(Callstack_depth+1, "run") << "reciprocal of x/m32 into " << Xname[dest] << end(); + const float* src = effective_address_float(modrm); + Xmm[dest] = 1.0 / *src; + trace(Callstack_depth+1, "run") << Xname[dest] << " is now " << Xmm[dest] << end(); + break; +} + +//:: square root + +:(before "End Initialize Op Names") +put_new(Name_f3_0f, "51", "square root of float (sqrtss)"); + +:(code) +void test_sqrtss() { + Xmm[1] = 2.0; + run( + "== code 0x1\n" + // op ModR/M SIB displacement immediate + "f3 0f 51 c1 \n" + // ModR/M in binary: 11 (direct mode) 000 (XMM0) 001 (XMM1) + ); + CHECK_TRACE_CONTENTS( + "run: square root of x/m32 into XMM0\n" + "run: x/m32 is XMM1\n" + "run: XMM0 is now 1.41421\n" + ); +} + +:(before "End Three-Byte Opcodes Starting With f3 0f") +case 0x51: { // square root of x/m32 into x32 + const uint8_t modrm = next(); + const uint8_t dest = (modrm>>3)&0x7; + trace(Callstack_depth+1, "run") << "square root of x/m32 into " << Xname[dest] << end(); + const float* src = effective_address_float(modrm); + Xmm[dest] = sqrt(*src); + trace(Callstack_depth+1, "run") << Xname[dest] << " is now " << Xmm[dest] << end(); + break; +} + +:(before "End Includes") +#include <math.h> + +//:: inverse square root + +:(before "End Initialize Op Names") +put_new(Name_f3_0f, "52", "inverse square root of float (rsqrtss)"); + +:(code) +void test_rsqrtss() { + Xmm[1] = 0.01; + run( + "== code 0x1\n" + // op ModR/M SIB displacement immediate + "f3 0f 52 c1 \n" + // ModR/M in binary: 11 (direct mode) 000 (XMM0) 001 (XMM1) + ); + CHECK_TRACE_CONTENTS( + "run: inverse square root of x/m32 into XMM0\n" + "run: x/m32 is XMM1\n" + "run: XMM0 is now 10\n" + ); +} + +:(before "End Three-Byte Opcodes Starting With f3 0f") +case 0x52: { // inverse square root of x/m32 into x32 + const uint8_t modrm = next(); + const uint8_t dest = (modrm>>3)&0x7; + trace(Callstack_depth+1, "run") << "inverse square root of x/m32 into " << Xname[dest] << end(); + const float* src = effective_address_float(modrm); + Xmm[dest] = 1.0 / sqrt(*src); + trace(Callstack_depth+1, "run") << Xname[dest] << " is now " << Xmm[dest] << end(); + break; +} + +:(code) +float* effective_address_float(uint8_t modrm) { + const uint8_t mod = (modrm>>6); + // ignore middle 3 'reg opcode' bits + const uint8_t rm = modrm & 0x7; + if (mod == 3) { + // mod 3 is just register direct addressing + trace(Callstack_depth+1, "run") << "x/m32 is " << Xname[rm] << end(); + return &Xmm[rm]; + } + uint32_t addr = effective_address_number(modrm); + trace(Callstack_depth+1, "run") << "effective address contains " << read_mem_f32(addr) << end(); + return mem_addr_f32(addr); +} + +//: compare + +:(before "End Initialize Op Names") +put_new(Name_0f, "2f", "compare: set CF if x32 < xm32 (comiss)"); + +:(code) +void test_compare_x32_with_mem_at_rm32() { + Reg[EAX].i = 0x2000; + Xmm[3] = 0.5; + run( + "== code 0x1\n" + // op ModR/M SIB displacement immediate + " 0f 2f 18 \n" // compare XMM3 with *EAX + // ModR/M in binary: 00 (indirect mode) 011 (lhs XMM3) 000 (rhs EAX) + "== data 0x2000\n" + "00 00 00 00\n" // 0x00000000 = 0.0 + ); + CHECK_TRACE_CONTENTS( + "run: compare XMM3 with x/m32\n" + "run: effective address is 0x00002000 (EAX)\n" + "run: SF=0; ZF=0; CF=0; OF=0\n" + ); +} + +:(before "End Two-Byte Opcodes Starting With 0f") +case 0x2f: { // set CF if x32 < x/m32 + const uint8_t modrm = next(); + const uint8_t reg1 = (modrm>>3)&0x7; + trace(Callstack_depth+1, "run") << "compare " << Xname[reg1] << " with x/m32" << end(); + const float* arg2 = effective_address_float(modrm); + // Flag settings carefully copied from the Intel manual. + // See also https://stackoverflow.com/questions/7057501/x86-assembler-floating-point-compare/7057771#7057771 + SF = ZF = CF = OF = false; + if (Xmm[reg1] == *arg2) ZF = true; + if (Xmm[reg1] < *arg2) CF = true; + trace(Callstack_depth+1, "run") << "SF=" << SF << "; ZF=" << ZF << "; CF=" << CF << "; OF=" << OF << end(); + break; +} |