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[NON4KPAGE] AllocLoadElfMemory multiblocks wrong alignment
Hi,
[jtreg testcase](https://github.com/openjdk/jdk/blob/master/test/hotspot/jtreg/vmTestbase/vm/jit/LongTransitions/libLTTest.cpp#L3397) `objdump -d /your/path/jdk/build/linux-x86_64-server-release/images/test/hotspot/jtreg/native/libLTTest.so `
```
0000000000046b50 <Java_vm_jit_LongTransitions_LTTest_nativeFnc52>:
46b50: 55 push %rbp
...
=> 47fff: b8 01 00 00 00 mov $0x1,%eax
^--- expected
48004: e8 67 a0 fb ff callq 2070 <fprintf@plt>
...
```
[AllocLoadElfMemory multiblocks wrong alignment](https://github.com/ptitSeb/box64/blob/main/src/elfs/elfloader.c#L302) failed to decode `0x3f00047fff` expected `B8 01 00 00 00`:
```
...
[BOX64] New Instruction x64:0x3f00047fff, native:0xffc8d68628
=> [BOX64] 0x3f00047fff: B8 00 00 00 00 MOV Reg, Id
^--- wrong
[BOX64] 0xffc8d68628: 1 emitted opcodes, inst=631, barrier=0 state=0/1(0), set=0/0, use=0, need=80/80, fuse=0, sm=0(0/0), pred=630, last_ip=0x3f00047fed Q0:XMM0
0380000c ORI xRAX_r12, xZR, 0x0
...
```
After changed the `balign` with `box64_pagesize`:
```
diff --git a/src/elfs/elfloader.c b/src/elfs/elfloader.c
index 2dadbda4..91b1df2e 100644
--- a/src/elfs/elfloader.c
+++ b/src/elfs/elfloader.c
@@ -299,8 +299,8 @@ int AllocLoadElfMemory(box64context_t* context, elfheader_t* head, int mainbin)
uint8_t prot = ((e->p_flags & PF_R)?PROT_READ:0)|((e->p_flags & PF_W)?PROT_WRITE:0)|((e->p_flags & PF_X)?PROT_EXEC:0);
// check if alignment is correct
uintptr_t balign = head->multiblocks[n].align-1;
- if(balign<4095) balign = 4095;
- head->multiblocks[n].asize = (e->p_memsz+(e->p_paddr&balign)+4095)&~4095;
+ if (balign < (box64_pagesize - 1)) balign = box64_pagesize - 1;
+ head->multiblocks[n].asize = (e->p_memsz + (e->p_paddr & balign) + (box64_pagesize - 1)) & ~(box64_pagesize - 1);
int try_mmap = 1;
if(e->p_paddr&balign)
try_mmap = 0;
```
Decoded `0x3f00047fff` correctly:
```
...
[BOX64] New Instruction x64:0x3f00047fff, native:0xffc8d68628
=> [BOX64] 0x3f00047fff: B8 01 00 00 00 MOV Reg, Id
^--- correct
[BOX64] 0xffc8d68628: 2 emitted opcodes, inst=631, barrier=0 state=0/1(0), set=0/0, use=0, need=0/0, fuse=0, sm=0(0/0), pred=630, last_ip=0x3f00047fed Q0:XMM0
0380040c ORI xRAX_r12, xZR, 0x1
...
```
Thanks,
Leslie Zhai
|
