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llvm-project/llvm/test/CodeGen/X86/xray-tail-call-sled.ll

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[XRay] Detect and emit sleds for sibling/tail calls Summary: This change promotes the 'isTailCall(...)' member function to TargetInstrInfo as a query interface for determining on a per-target basis whether a given MachineInstr is a tail call instruction. We build upon this in the XRay instrumentation pass to emit special sleds for tail call optimisations, where we emit the correct kind of sled. The tail call sleds look like a mix between the function entry and function exit sleds. Form-wise, the sled comes before the "jmp" instruction that implements the tail call similar to how we do it for the function entry sled. Functionally, because we know this is a tail call, it behaves much like an exit sled -- i.e. at runtime we may use the exit trampolines instead of a different kind of trampoline. A follow-up change to recognise these sleds will be done in compiler-rt, so that we can start intercepting these initially as exits, but also have the option to have different log entries to more accurately reflect that this is actually a tail call. Reviewers: echristo, rSerge, majnemer Subscribers: mehdi_amini, dberris, llvm-commits Differential Revision: https://reviews.llvm.org/D23986 llvm-svn: 280334
2016-09-01 09:29:13 +08:00
; RUN: llc -filetype=asm -o - -mtriple=x86_64-unknown-linux-gnu < %s | FileCheck %s
[xray] Add XRay support for Mach-O in CodeGen Currently, XRay only supports emitting the XRay table (xray_instr_map) on ELF binaries. Let's add Mach-O support. Differential Revision: https://reviews.llvm.org/D26983 llvm-svn: 287734
2016-11-23 10:07:04 +08:00
; RUN: llc -filetype=asm -o - -mtriple=x86_64-darwin-unknown < %s | FileCheck %s
[XRay] Detect and emit sleds for sibling/tail calls Summary: This change promotes the 'isTailCall(...)' member function to TargetInstrInfo as a query interface for determining on a per-target basis whether a given MachineInstr is a tail call instruction. We build upon this in the XRay instrumentation pass to emit special sleds for tail call optimisations, where we emit the correct kind of sled. The tail call sleds look like a mix between the function entry and function exit sleds. Form-wise, the sled comes before the "jmp" instruction that implements the tail call similar to how we do it for the function entry sled. Functionally, because we know this is a tail call, it behaves much like an exit sled -- i.e. at runtime we may use the exit trampolines instead of a different kind of trampoline. A follow-up change to recognise these sleds will be done in compiler-rt, so that we can start intercepting these initially as exits, but also have the option to have different log entries to more accurately reflect that this is actually a tail call. Reviewers: echristo, rSerge, majnemer Subscribers: mehdi_amini, dberris, llvm-commits Differential Revision: https://reviews.llvm.org/D23986 llvm-svn: 280334
2016-09-01 09:29:13 +08:00
define i32 @callee() nounwind noinline uwtable "function-instrument"="xray-always" {
; CHECK: .p2align 1, 0x90
; CHECK-LABEL: Lxray_sled_0:
[XRay][CodeGen] Use PIC-friendly code in XRay sleds and remove synthetic references in .text Summary: This is a re-roll of D36615 which uses PLT relocations in the back-end to the call to __xray_CustomEvent() when building in -fPIC and -fxray-instrument mode. Reviewers: pcc, djasper, bkramer Subscribers: sdardis, javed.absar, llvm-commits Differential Revision: https://reviews.llvm.org/D37373 llvm-svn: 312466
2017-09-04 13:34:58 +08:00
; CHECK: .ascii "\353\t"
[XRay] Detect and emit sleds for sibling/tail calls Summary: This change promotes the 'isTailCall(...)' member function to TargetInstrInfo as a query interface for determining on a per-target basis whether a given MachineInstr is a tail call instruction. We build upon this in the XRay instrumentation pass to emit special sleds for tail call optimisations, where we emit the correct kind of sled. The tail call sleds look like a mix between the function entry and function exit sleds. Form-wise, the sled comes before the "jmp" instruction that implements the tail call similar to how we do it for the function entry sled. Functionally, because we know this is a tail call, it behaves much like an exit sled -- i.e. at runtime we may use the exit trampolines instead of a different kind of trampoline. A follow-up change to recognise these sleds will be done in compiler-rt, so that we can start intercepting these initially as exits, but also have the option to have different log entries to more accurately reflect that this is actually a tail call. Reviewers: echristo, rSerge, majnemer Subscribers: mehdi_amini, dberris, llvm-commits Differential Revision: https://reviews.llvm.org/D23986 llvm-svn: 280334
2016-09-01 09:29:13 +08:00
; CHECK-NEXT: nopw 512(%rax,%rax)
ret i32 0
; CHECK: .p2align 1, 0x90
; CHECK-LABEL: Lxray_sled_1:
[XRay][CodeGen] Use PIC-friendly code in XRay sleds and remove synthetic references in .text Summary: This is a re-roll of D36615 which uses PLT relocations in the back-end to the call to __xray_CustomEvent() when building in -fPIC and -fxray-instrument mode. Reviewers: pcc, djasper, bkramer Subscribers: sdardis, javed.absar, llvm-commits Differential Revision: https://reviews.llvm.org/D37373 llvm-svn: 312466
2017-09-04 13:34:58 +08:00
; CHECK: retq
[XRay] Detect and emit sleds for sibling/tail calls Summary: This change promotes the 'isTailCall(...)' member function to TargetInstrInfo as a query interface for determining on a per-target basis whether a given MachineInstr is a tail call instruction. We build upon this in the XRay instrumentation pass to emit special sleds for tail call optimisations, where we emit the correct kind of sled. The tail call sleds look like a mix between the function entry and function exit sleds. Form-wise, the sled comes before the "jmp" instruction that implements the tail call similar to how we do it for the function entry sled. Functionally, because we know this is a tail call, it behaves much like an exit sled -- i.e. at runtime we may use the exit trampolines instead of a different kind of trampoline. A follow-up change to recognise these sleds will be done in compiler-rt, so that we can start intercepting these initially as exits, but also have the option to have different log entries to more accurately reflect that this is actually a tail call. Reviewers: echristo, rSerge, majnemer Subscribers: mehdi_amini, dberris, llvm-commits Differential Revision: https://reviews.llvm.org/D23986 llvm-svn: 280334
2016-09-01 09:29:13 +08:00
; CHECK-NEXT: nopw %cs:512(%rax,%rax)
}
[XRay][CodeGen] Use PIC-friendly code in XRay sleds and remove synthetic references in .text Summary: This is a re-roll of D36615 which uses PLT relocations in the back-end to the call to __xray_CustomEvent() when building in -fPIC and -fxray-instrument mode. Reviewers: pcc, djasper, bkramer Subscribers: sdardis, javed.absar, llvm-commits Differential Revision: https://reviews.llvm.org/D37373 llvm-svn: 312466
2017-09-04 13:34:58 +08:00
; CHECK-LABEL: xray_instr_map
[XRay] Reduce synthetic references emitted by XRay Summary: When we're building with XRay instrumentation, we use a trick that preserves references from the function to a function sled index. This index table lives in a separate section, and without this trick the linker is free to garbage-collect this section and all the segments it refers to. Until we're able to tell the linkers to preserve these sections, we use this reference trick to keep around both the index and the entries in the instrumentation map. Before this change we emitted both a synthetic reference to the label in the instrumentation map, and to the entry in the function map index. This change removes the first synthetic reference and only emits one synthetic reference to the index -- the index entry has the references to the labels in the instrumentation map, so the linker will still preserve those if the function itself is preserved. This reduces the amount of synthetic references we emit from 16 bytes to just 8 bytes in x86_64, and similarly to other platforms. Reviewers: dblaikie Subscribers: javed.absar, kpw, pelikan, llvm-commits Differential Revision: https://reviews.llvm.org/D34340 llvm-svn: 305880
2017-06-21 14:39:42 +08:00
; CHECK-LABEL: Lxray_sleds_start0:
[xray] Add XRay support for Mach-O in CodeGen Currently, XRay only supports emitting the XRay table (xray_instr_map) on ELF binaries. Let's add Mach-O support. Differential Revision: https://reviews.llvm.org/D26983 llvm-svn: 287734
2016-11-23 10:07:04 +08:00
; CHECK: .quad {{.*}}xray_sled_0
; CHECK: .quad {{.*}}xray_sled_1
[XRay] Reduce synthetic references emitted by XRay Summary: When we're building with XRay instrumentation, we use a trick that preserves references from the function to a function sled index. This index table lives in a separate section, and without this trick the linker is free to garbage-collect this section and all the segments it refers to. Until we're able to tell the linkers to preserve these sections, we use this reference trick to keep around both the index and the entries in the instrumentation map. Before this change we emitted both a synthetic reference to the label in the instrumentation map, and to the entry in the function map index. This change removes the first synthetic reference and only emits one synthetic reference to the index -- the index entry has the references to the labels in the instrumentation map, so the linker will still preserve those if the function itself is preserved. This reduces the amount of synthetic references we emit from 16 bytes to just 8 bytes in x86_64, and similarly to other platforms. Reviewers: dblaikie Subscribers: javed.absar, kpw, pelikan, llvm-commits Differential Revision: https://reviews.llvm.org/D34340 llvm-svn: 305880
2017-06-21 14:39:42 +08:00
; CHECK-LABEL: Lxray_sleds_end0:
[XRay][CodeGen] Use PIC-friendly code in XRay sleds and remove synthetic references in .text Summary: This is a re-roll of D36615 which uses PLT relocations in the back-end to the call to __xray_CustomEvent() when building in -fPIC and -fxray-instrument mode. Reviewers: pcc, djasper, bkramer Subscribers: sdardis, javed.absar, llvm-commits Differential Revision: https://reviews.llvm.org/D37373 llvm-svn: 312466
2017-09-04 13:34:58 +08:00
; CHECK-LABEL: xray_fn_idx
[XRay] Reduce synthetic references emitted by XRay Summary: When we're building with XRay instrumentation, we use a trick that preserves references from the function to a function sled index. This index table lives in a separate section, and without this trick the linker is free to garbage-collect this section and all the segments it refers to. Until we're able to tell the linkers to preserve these sections, we use this reference trick to keep around both the index and the entries in the instrumentation map. Before this change we emitted both a synthetic reference to the label in the instrumentation map, and to the entry in the function map index. This change removes the first synthetic reference and only emits one synthetic reference to the index -- the index entry has the references to the labels in the instrumentation map, so the linker will still preserve those if the function itself is preserved. This reduces the amount of synthetic references we emit from 16 bytes to just 8 bytes in x86_64, and similarly to other platforms. Reviewers: dblaikie Subscribers: javed.absar, kpw, pelikan, llvm-commits Differential Revision: https://reviews.llvm.org/D34340 llvm-svn: 305880
2017-06-21 14:39:42 +08:00
; CHECK: .quad {{.*}}xray_sleds_start0
; CHECK-NEXT: .quad {{.*}}xray_sleds_end0
[XRay] Detect and emit sleds for sibling/tail calls Summary: This change promotes the 'isTailCall(...)' member function to TargetInstrInfo as a query interface for determining on a per-target basis whether a given MachineInstr is a tail call instruction. We build upon this in the XRay instrumentation pass to emit special sleds for tail call optimisations, where we emit the correct kind of sled. The tail call sleds look like a mix between the function entry and function exit sleds. Form-wise, the sled comes before the "jmp" instruction that implements the tail call similar to how we do it for the function entry sled. Functionally, because we know this is a tail call, it behaves much like an exit sled -- i.e. at runtime we may use the exit trampolines instead of a different kind of trampoline. A follow-up change to recognise these sleds will be done in compiler-rt, so that we can start intercepting these initially as exits, but also have the option to have different log entries to more accurately reflect that this is actually a tail call. Reviewers: echristo, rSerge, majnemer Subscribers: mehdi_amini, dberris, llvm-commits Differential Revision: https://reviews.llvm.org/D23986 llvm-svn: 280334
2016-09-01 09:29:13 +08:00
define i32 @caller() nounwind noinline uwtable "function-instrument"="xray-always" {
; CHECK: .p2align 1, 0x90
; CHECK-LABEL: Lxray_sled_2:
[XRay][CodeGen] Use PIC-friendly code in XRay sleds and remove synthetic references in .text Summary: This is a re-roll of D36615 which uses PLT relocations in the back-end to the call to __xray_CustomEvent() when building in -fPIC and -fxray-instrument mode. Reviewers: pcc, djasper, bkramer Subscribers: sdardis, javed.absar, llvm-commits Differential Revision: https://reviews.llvm.org/D37373 llvm-svn: 312466
2017-09-04 13:34:58 +08:00
; CHECK: .ascii "\353\t"
[XRay] Detect and emit sleds for sibling/tail calls Summary: This change promotes the 'isTailCall(...)' member function to TargetInstrInfo as a query interface for determining on a per-target basis whether a given MachineInstr is a tail call instruction. We build upon this in the XRay instrumentation pass to emit special sleds for tail call optimisations, where we emit the correct kind of sled. The tail call sleds look like a mix between the function entry and function exit sleds. Form-wise, the sled comes before the "jmp" instruction that implements the tail call similar to how we do it for the function entry sled. Functionally, because we know this is a tail call, it behaves much like an exit sled -- i.e. at runtime we may use the exit trampolines instead of a different kind of trampoline. A follow-up change to recognise these sleds will be done in compiler-rt, so that we can start intercepting these initially as exits, but also have the option to have different log entries to more accurately reflect that this is actually a tail call. Reviewers: echristo, rSerge, majnemer Subscribers: mehdi_amini, dberris, llvm-commits Differential Revision: https://reviews.llvm.org/D23986 llvm-svn: 280334
2016-09-01 09:29:13 +08:00
; CHECK-NEXT: nopw 512(%rax,%rax)
; CHECK: .p2align 1, 0x90
; CHECK-LABEL: Lxray_sled_3:
; CHECK-NEXT: .ascii "\353\t"
; CHECK-NEXT: nopw 512(%rax,%rax)
%retval = tail call i32 @callee()
[xray] Add XRay support for Mach-O in CodeGen Currently, XRay only supports emitting the XRay table (xray_instr_map) on ELF binaries. Let's add Mach-O support. Differential Revision: https://reviews.llvm.org/D26983 llvm-svn: 287734
2016-11-23 10:07:04 +08:00
; CHECK: jmp {{.*}}callee {{.*}}# TAILCALL
[XRay] Detect and emit sleds for sibling/tail calls Summary: This change promotes the 'isTailCall(...)' member function to TargetInstrInfo as a query interface for determining on a per-target basis whether a given MachineInstr is a tail call instruction. We build upon this in the XRay instrumentation pass to emit special sleds for tail call optimisations, where we emit the correct kind of sled. The tail call sleds look like a mix between the function entry and function exit sleds. Form-wise, the sled comes before the "jmp" instruction that implements the tail call similar to how we do it for the function entry sled. Functionally, because we know this is a tail call, it behaves much like an exit sled -- i.e. at runtime we may use the exit trampolines instead of a different kind of trampoline. A follow-up change to recognise these sleds will be done in compiler-rt, so that we can start intercepting these initially as exits, but also have the option to have different log entries to more accurately reflect that this is actually a tail call. Reviewers: echristo, rSerge, majnemer Subscribers: mehdi_amini, dberris, llvm-commits Differential Revision: https://reviews.llvm.org/D23986 llvm-svn: 280334
2016-09-01 09:29:13 +08:00
ret i32 %retval
}
[XRay][CodeGen] Use PIC-friendly code in XRay sleds and remove synthetic references in .text Summary: This is a re-roll of D36615 which uses PLT relocations in the back-end to the call to __xray_CustomEvent() when building in -fPIC and -fxray-instrument mode. Reviewers: pcc, djasper, bkramer Subscribers: sdardis, javed.absar, llvm-commits Differential Revision: https://reviews.llvm.org/D37373 llvm-svn: 312466
2017-09-04 13:34:58 +08:00
; CHECK-LABEL: xray_instr_map
[XRay] Reduce synthetic references emitted by XRay Summary: When we're building with XRay instrumentation, we use a trick that preserves references from the function to a function sled index. This index table lives in a separate section, and without this trick the linker is free to garbage-collect this section and all the segments it refers to. Until we're able to tell the linkers to preserve these sections, we use this reference trick to keep around both the index and the entries in the instrumentation map. Before this change we emitted both a synthetic reference to the label in the instrumentation map, and to the entry in the function map index. This change removes the first synthetic reference and only emits one synthetic reference to the index -- the index entry has the references to the labels in the instrumentation map, so the linker will still preserve those if the function itself is preserved. This reduces the amount of synthetic references we emit from 16 bytes to just 8 bytes in x86_64, and similarly to other platforms. Reviewers: dblaikie Subscribers: javed.absar, kpw, pelikan, llvm-commits Differential Revision: https://reviews.llvm.org/D34340 llvm-svn: 305880
2017-06-21 14:39:42 +08:00
; CHECK-LABEL: Lxray_sleds_start1:
[xray] Add XRay support for Mach-O in CodeGen Currently, XRay only supports emitting the XRay table (xray_instr_map) on ELF binaries. Let's add Mach-O support. Differential Revision: https://reviews.llvm.org/D26983 llvm-svn: 287734
2016-11-23 10:07:04 +08:00
; CHECK: .quad {{.*}}xray_sled_2
; CHECK: .quad {{.*}}xray_sled_3
[XRay] Reduce synthetic references emitted by XRay Summary: When we're building with XRay instrumentation, we use a trick that preserves references from the function to a function sled index. This index table lives in a separate section, and without this trick the linker is free to garbage-collect this section and all the segments it refers to. Until we're able to tell the linkers to preserve these sections, we use this reference trick to keep around both the index and the entries in the instrumentation map. Before this change we emitted both a synthetic reference to the label in the instrumentation map, and to the entry in the function map index. This change removes the first synthetic reference and only emits one synthetic reference to the index -- the index entry has the references to the labels in the instrumentation map, so the linker will still preserve those if the function itself is preserved. This reduces the amount of synthetic references we emit from 16 bytes to just 8 bytes in x86_64, and similarly to other platforms. Reviewers: dblaikie Subscribers: javed.absar, kpw, pelikan, llvm-commits Differential Revision: https://reviews.llvm.org/D34340 llvm-svn: 305880
2017-06-21 14:39:42 +08:00
; CHECK-LABEL: Lxray_sleds_end1:
[XRay][CodeGen] Use PIC-friendly code in XRay sleds and remove synthetic references in .text Summary: This is a re-roll of D36615 which uses PLT relocations in the back-end to the call to __xray_CustomEvent() when building in -fPIC and -fxray-instrument mode. Reviewers: pcc, djasper, bkramer Subscribers: sdardis, javed.absar, llvm-commits Differential Revision: https://reviews.llvm.org/D37373 llvm-svn: 312466
2017-09-04 13:34:58 +08:00
; CHECK-LABEL: xray_fn_idx
[XRay] Reduce synthetic references emitted by XRay Summary: When we're building with XRay instrumentation, we use a trick that preserves references from the function to a function sled index. This index table lives in a separate section, and without this trick the linker is free to garbage-collect this section and all the segments it refers to. Until we're able to tell the linkers to preserve these sections, we use this reference trick to keep around both the index and the entries in the instrumentation map. Before this change we emitted both a synthetic reference to the label in the instrumentation map, and to the entry in the function map index. This change removes the first synthetic reference and only emits one synthetic reference to the index -- the index entry has the references to the labels in the instrumentation map, so the linker will still preserve those if the function itself is preserved. This reduces the amount of synthetic references we emit from 16 bytes to just 8 bytes in x86_64, and similarly to other platforms. Reviewers: dblaikie Subscribers: javed.absar, kpw, pelikan, llvm-commits Differential Revision: https://reviews.llvm.org/D34340 llvm-svn: 305880
2017-06-21 14:39:42 +08:00
; CHECK: .quad {{.*}}xray_sleds_start1
; CHECK: .quad {{.*}}xray_sleds_end1