| // XFAIL:* |
| //// Suboptimal coverage, see description below. |
| |
| // REQUIRES: lldb |
| // UNSUPPORTED: system-windows |
| // RUN: %dexter --fail-lt 1.0 -w --debugger lldb \ |
| // RUN: --builder 'clang-c' --cflags "-O3 -glldb" -- %s |
| |
| //// Adapted from https://bugs.llvm.org/show_bug.cgi?id=34136#c1 |
| //// LowerDbgDeclare has since been updated to look through bitcasts. We still |
| //// get suboptimal coverage at the beginning of 'main' though. For each local, |
| //// LowerDbgDeclare inserts a dbg.value and a dbg.value+DW_OP_deref before the |
| //// store (after the call to 'getint') and the call to 'alias' respectively. |
| //// The first dbg.value describes the result of the 'getint' call, eventually |
| //// becoming a register location. The second points back into the stack |
| //// home. There is a gap in the coverage between the quickly clobbered register |
| //// location and the stack location, even though the stack location is valid |
| //// during that gap. For x86 we end up with this code at the start of main: |
| //// 00000000004004b0 <main>: |
| //// 4004b0: sub rsp,0x18 |
| //// 4004b4: mov edi,0x5 |
| //// 4004b9: call 400480 <getint> |
| //// 4004be: mov DWORD PTR [rsp+0x14],eax |
| //// 4004c2: mov edi,0x5 |
| //// 4004c7: call 400480 <getint> |
| //// 4004cc: mov DWORD PTR [rsp+0x10],eax |
| //// 4004d0: mov edi,0x5 |
| //// 4004d5: call 400480 <getint> |
| //// 4004da: mov DWORD PTR [rsp+0xc],eax |
| //// ... |
| //// With these variable locations: |
| //// DW_TAG_variable |
| //// DW_AT_location (0x00000000: |
| //// [0x00000000004004be, 0x00000000004004cc): DW_OP_reg0 RAX |
| //// [0x00000000004004de, 0x0000000000400503): DW_OP_breg7 RSP+20) |
| //// DW_AT_name ("x") |
| //// ... |
| //// DW_TAG_variable |
| //// DW_AT_location (0x00000037: |
| //// [0x00000000004004cc, 0x00000000004004da): DW_OP_reg0 RAX |
| //// [0x00000000004004e8, 0x0000000000400503): DW_OP_breg7 RSP+16) |
| //// DW_AT_name ("y") |
| //// ... |
| //// DW_TAG_variable |
| //// DW_AT_location (0x0000006e: |
| //// [0x00000000004004da, 0x00000000004004e8): DW_OP_reg0 RAX |
| //// [0x00000000004004f2, 0x0000000000400503): DW_OP_breg7 RSP+12) |
| //// DW_AT_name ("z") |
| //// ... |
| |
| char g = 1; |
| int five = 5; |
| __attribute__((__noinline__)) |
| int getint(int x) { |
| g = x - 4; |
| return x * g; |
| } |
| |
| __attribute__((__noinline__)) |
| void alias(char* c) { |
| g = *c; |
| *c = (char)five; |
| } |
| |
| int main() { |
| int x = getint(5); |
| int y = getint(5); // DexLabel('s1') |
| int z = getint(5); // DexLabel('s2') |
| alias((char*)&x); // DexLabel('s3') |
| alias((char*)&y); |
| alias((char*)&z); |
| return 0; // DexLabel('s4') |
| } |
| |
| // DexExpectWatchValue('x', '5', from_line=ref('s1'), to_line=ref('s4')) |
| // DexExpectWatchValue('y', '5', from_line=ref('s2'), to_line=ref('s4')) |
| // DexExpectWatchValue('z', '5', from_line=ref('s3'), to_line=ref('s4')) |
