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Apologies to dyn_x86. Instead of depending on mere typecasting, actually mask and compare to determine whether &cpu_regs resides above 4GB address-wise so the correct x86_64 executable code is generated.

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Jonathan Campbell
2020-11-27 22:14:17 -08:00
parent 91ad7e61ae
commit 15d5114d62
2 changed files with 4 additions and 2 deletions
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4
src/cpu/core_dyn_x86/risc_x64.h
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@@ -281,7 +281,9 @@ static BlockReturn gen_runcodeInit(uint8_t *code) {
opcode(15).Emit8Reg(0x50); // push r15
opcode(14).Emit8Reg(0x50); // push r14
// mov rbp, &cpu_regs
if ((uint32_t)(Bitu)&cpu_regs == (Bitu)&cpu_regs) opcode(5).setimm((Bitu)&cpu_regs,4).Emit8Reg(0xB8);
/* NTS: For VS2019, mere typecasting won't correctly detect whether the pointer is small enough to fit in 32 bits.
We have to mask and compare. If the pointer is above 4GB and the wrong choice is made, dynamic core will crash. --J.C. */
if ((((Bitu)&cpu_regs) && (Bitu)0xFFFFFFFFul) == (Bitu)&cpu_regs) opcode(5).setimm((Bitu)&cpu_regs,4).Emit8Reg(0xB8);
else opcode(5).set64().setimm((Bitu)&cpu_regs,8).Emit8Reg(0xB8);
opcode(13).Emit8Reg(0x50); // push r13
opcode(12).Emit8Reg(0x50); // push r12

2
vs2015/config.h
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@@ -77,7 +77,7 @@
/* The type of cpu this target has */
# define C_TARGETCPU X86_64
/* Define to 1 to use x86 dynamic cpu core */
# undef C_DYNAMIC_X86 /* Sorry, dyn_x86 is crashing in 64-bit builds under VS2019 */
# define C_DYNAMIC_X86 1
# define C_DYNREC 1
#elif defined (_M_ARM64) || defined (_M_ARM) /* Microsoft C++ amd64, arm32 and arm64 */
# undef C_TARGETCPU