While future gas versions will allow line number information to be generated for all instances of .irp and alike [1][2], the same isn't true (nor immediately intended) for .macro [3]. Hence macros, when they do more than just invoke another macro or issue an individual insn, want to have .line directives (in header files also .file ones) in place.
Signed-off-by: Jan Beulich <[email protected]> [1] https://sourceware.org/git?p=binutils-gdb.git;a=commitdiff;h=7992631e8c0b0e711fbaba991348ef6f6e583725 [2] https://sourceware.org/git?p=binutils-gdb.git;a=commitdiff;h=2ee1792bec225ea19c71095cee5a3a9ae6df7c59 [3] https://sourceware.org/git?p=binutils-gdb.git;a=commitdiff;h=6d1ace6861e999361b30d1bc27459ab8094e0d4a --- Using .file has the perhaps undesirable side effect of generating a fair amount of (all identical) STT_FILE entries in the symbol table. We also can't use the supposedly assembler-internal (and hence undocumented) .appfile anymore, as it was removed [4]. Note that .linefile (also internal/undocumented) as well as the "# <line> <file>" constructs the compiler emits, leading to .linefile insertion by the assembler, aren't of use anyway as these are processed and purged when processing .macro [3]. [4] https://sourceware.org/git?p=binutils-gdb.git;a=commitdiff;h=c39e89c3aaa3a6790f85e80f2da5022bc4bce38b --- a/xen/arch/x86/include/asm/spec_ctrl_asm.h +++ b/xen/arch/x86/include/asm/spec_ctrl_asm.h @@ -24,6 +24,8 @@ #include <asm/msr-index.h> #include <asm/spec_ctrl.h> +#define FILE_AND_LINE .file __FILE__; .line __LINE__ + /* * Saving and restoring MSR_SPEC_CTRL state is a little tricky. * @@ -89,6 +91,7 @@ */ .macro DO_OVERWRITE_RSB tmp=rax + FILE_AND_LINE /* * Requires nothing * Clobbers \tmp (%rax by default), %rcx @@ -137,6 +140,7 @@ .endm .macro DO_SPEC_CTRL_ENTRY maybexen:req + FILE_AND_LINE /* * Requires %rsp=regs (also cpuinfo if !maybexen) * Requires %r14=stack_end (if maybexen) @@ -171,6 +175,7 @@ .endm .macro DO_SPEC_CTRL_EXIT_TO_XEN + FILE_AND_LINE /* * Requires %rbx=stack_end * Clobbers %rax, %rcx, %rdx @@ -192,6 +197,7 @@ .endm .macro DO_SPEC_CTRL_EXIT_TO_GUEST + FILE_AND_LINE /* * Requires %eax=spec_ctrl, %rsp=regs/cpuinfo * Clobbers %rcx, %rdx @@ -241,6 +247,7 @@ * been reloaded. */ .macro SPEC_CTRL_ENTRY_FROM_INTR_IST + FILE_AND_LINE /* * Requires %rsp=regs, %r14=stack_end * Clobbers %rax, %rcx, %rdx @@ -288,6 +295,7 @@ UNLIKELY_DISPATCH_LABEL(\@_serialise): /* Use when exiting to Xen in IST context. */ .macro SPEC_CTRL_EXIT_TO_XEN_IST + FILE_AND_LINE /* * Requires %rbx=stack_end * Clobbers %rax, %rcx, %rdx --- a/xen/arch/x86/indirect-thunk.S +++ b/xen/arch/x86/indirect-thunk.S @@ -12,6 +12,7 @@ #include <asm/asm_defns.h> .macro IND_THUNK_RETPOLINE reg:req + .line __LINE__ call 2f 1: lfence
