r280355 - [Frontend] Fix mcount inlining bug
Honggyu Kim via cfe-commits
cfe-commits at lists.llvm.org
Thu Sep 1 04:29:22 PDT 2016
Author: honggyu.kim
Date: Thu Sep 1 06:29:21 2016
New Revision: 280355
URL: http://llvm.org/viewvc/llvm-project?rev=280355&view=rev
Log:
[Frontend] Fix mcount inlining bug
Since some profiling tools, such as gprof, ftrace, and uftrace, use
-pg option to generate a mcount function call at the entry of each
function. Function invocation can be detected by this hook function.
But mcount insertion is done before function inlining phase in clang,
sometime a function that already has a mcount call can be inlined in the
middle of another function.
This patch adds an attribute "counting-function" to each function
rather than emitting the mcount call directly in frontend so that this
attribute can be processed in backend. Then the mcount calls can be
properly inserted in backend after all the other optimizations are
completed.
Link: https://llvm.org/bugs/show_bug.cgi?id=28660
Reviewers: hans, rjmccall, hfinkel, rengolin, compnerd
Subscribers: shenhan, cfe-commits
Differential Revision: https://reviews.llvm.org/D22666
Modified:
cfe/trunk/lib/CodeGen/CodeGenFunction.cpp
cfe/trunk/test/CodeGen/mcount.c
cfe/trunk/test/Frontend/gnu-mcount.c
Modified: cfe/trunk/lib/CodeGen/CodeGenFunction.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenFunction.cpp?rev=280355&r1=280354&r2=280355&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenFunction.cpp (original)
+++ cfe/trunk/lib/CodeGen/CodeGenFunction.cpp Thu Sep 1 06:29:21 2016
@@ -428,14 +428,6 @@ void CodeGenFunction::EmitFunctionInstru
EmitNounwindRuntimeCall(F, args);
}
-void CodeGenFunction::EmitMCountInstrumentation() {
- llvm::FunctionType *FTy = llvm::FunctionType::get(VoidTy, false);
-
- llvm::Constant *MCountFn =
- CGM.CreateRuntimeFunction(FTy, getTarget().getMCountName());
- EmitNounwindRuntimeCall(MCountFn);
-}
-
// OpenCL v1.2 s5.6.4.6 allows the compiler to store kernel argument
// information in the program executable. The argument information stored
// includes the argument name, its type, the address and access qualifiers used.
@@ -794,8 +786,12 @@ void CodeGenFunction::StartFunction(Glob
if (ShouldInstrumentFunction())
EmitFunctionInstrumentation("__cyg_profile_func_enter");
+ // Since emitting the mcount call here impacts optimizations such as function
+ // inlining, we just add an attribute to insert a mcount call in backend.
+ // The attribute "counting-function" is set to mcount function name which is
+ // architecture dependent.
if (CGM.getCodeGenOpts().InstrumentForProfiling)
- EmitMCountInstrumentation();
+ Fn->addFnAttr("counting-function", getTarget().getMCountName());
if (RetTy->isVoidType()) {
// Void type; nothing to return.
Modified: cfe/trunk/test/CodeGen/mcount.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/mcount.c?rev=280355&r1=280354&r2=280355&view=diff
==============================================================================
--- cfe/trunk/test/CodeGen/mcount.c (original)
+++ cfe/trunk/test/CodeGen/mcount.c Thu Sep 1 06:29:21 2016
@@ -1,4 +1,5 @@
// RUN: %clang_cc1 -pg -triple i386-unknown-unknown -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -pg -triple i386-unknown-unknown -emit-llvm -O2 -o - %s | FileCheck %s
// RUN: %clang_cc1 -pg -triple powerpc-unknown-gnu-linux -emit-llvm -o - %s | FileCheck -check-prefix=CHECK-PREFIXED %s
// RUN: %clang_cc1 -pg -triple powerpc64-unknown-gnu-linux -emit-llvm -o - %s | FileCheck -check-prefix=CHECK-PREFIXED %s
// RUN: %clang_cc1 -pg -triple powerpc64le-unknown-gnu-linux -emit-llvm -o - %s | FileCheck -check-prefix=CHECK-PREFIXED %s
@@ -12,7 +13,20 @@
// RUN: %clang_cc1 -pg -triple powerpc64le-netbsd -emit-llvm -o - %s | FileCheck -check-prefix=CHECK-PREFIXED %s
// RUN: %clang_cc1 -pg -triple sparc-netbsd -emit-llvm -o - %s | FileCheck -check-prefix=CHECK-PREFIXED %s
// RUN: %clang_cc1 -pg -triple sparc64-netbsd -emit-llvm -o - %s | FileCheck -check-prefix=CHECK-PREFIXED %s
-void foo(void) {
-// CHECK: call void @mcount()
-// CHECK-PREFIXED: call void @_mcount()
+// RUN: %clang_cc1 -emit-llvm -o - %s | FileCheck %s -check-prefix=NO-MCOUNT
+
+int bar(void) {
+ return 0;
}
+
+int foo(void) {
+ return bar();
+}
+
+int main(void) {
+ return foo();
+}
+
+// CHECK: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="mcount"{{.*}} }
+// CHECK-PREFIXED: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="_mcount"{{.*}} }
+// NO-MCOUNT-NOT: attributes #{{[0-9]}} = { {{.*}}"counting-function"={{.*}} }
Modified: cfe/trunk/test/Frontend/gnu-mcount.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Frontend/gnu-mcount.c?rev=280355&r1=280354&r2=280355&view=diff
==============================================================================
--- cfe/trunk/test/Frontend/gnu-mcount.c (original)
+++ cfe/trunk/test/Frontend/gnu-mcount.c Thu Sep 1 06:29:21 2016
@@ -44,35 +44,35 @@ int f() {
}
// CHECK-LABEL: f
-// CHECK-ARM-IOS-NOT: call void @_mcount()
-// CHECK-ARM-IOS-NOT: call void @"\01__gnu_mcount_nc"()
-// CHECK-ARM-EABI: call void @"\01mcount"()
-// CHECK-ARM-EABI-NOT: call void @"\01__gnu_mcount_nc"()
-// CHECK-ARM64-EABI: call void @mcount()
-// CHECK-ARM64-EABI-MEABI-GNU: call void @"\01_mcount"()
-// CHECK-ARM64-EABI-NOT: call void @"\01__gnu_mcount_nc"()
-// CHECK-ARM-EABI-FREEBSD: call void @__mcount()
-// CHECK-ARM-EABI-FREEBSD-NOT: call void @"\01__gnu_mcount_nc"()
-// CHECK-ARM64-EABI-FREEBSD: call void @.mcount()
-// CHECK-ARM64-EABI-FREEBSD-NOT: call void @"\01__gnu_mcount_nc"()
-// CHECK-ARM-EABI-NETBSD: call void @_mcount()
-// CHECK-ARM-EABI-NETBSD-NOT: call void @"\01__gnu_mcount_nc"()
-// CHECK-ARM-EABI-OPENBSD: call void @__mcount()
-// CHECK-ARM-EABI-OPENBSD-NOT: call void @"\01__gnu_mcount_nc"()
-// CHECK-ARM64-EABI-OPENBSD: call void @mcount()
-// CHECK-ARM64-EABI-OPENBSD-NOT: call void @"\01__gnu_mcount_nc"()
-// CHECK-ARM-EABI-MEABI-GNU-NOT: call void @mcount()
-// CHECK-ARM-EABI-MEABI-GNU: call void @"\01__gnu_mcount_nc"()
-// CHECK-ARM-EABI-BITRIG: call void @__mcount()
-// CHECK-ARM-EABI-BITRIG-NOT: call void @"\01__gnu_mcount_nc"()
-// CHECK-ARM54-EABI-BITRIG: call void @mcount()
-// CHECK-ARM54-EABI-BITRIG-NOT: call void @"\01__gnu_mcount_nc"()
-// CHECK-ARM-EABI-RTEMS: call void @mcount()
-// CHECK-ARM-EABI-RTEMS-NOT: call void @"\01__gnu_mcount_nc"()
-// CHECK-ARM64-EABI-RTEMS: call void @mcount()
-// CHECK-ARM64-EABI-RTEMS-NOT: call void @"\01__gnu_mcount_nc"()
-// CHECK-ARM-EABI-CLOUDABI: call void @mcount()
-// CHECK-ARM-EABI-CLOUDABI-NOT: call void @"\01__gnu_mcount_nc"()
-// CHECK-ARM64-EABI-CLOUDABI: call void @mcount()
-// CHECK-ARM64-EABI-CLOUDABI-NOT: call void @"\01__gnu_mcount_nc"()
+// CHECK-ARM-IOS-NOT: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="_mcount"{{.*}} }
+// CHECK-ARM-IOS-NOT: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01__gnu_mcount_nc"{{.*}} }
+// CHECK-ARM-EABI: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01mcount"{{.*}} }
+// CHECK-ARM-EABI-NOT: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01__gnu_mcount_nc"{{.*}} }
+// CHECK-ARM64-EABI: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="mcount"{{.*}} }
+// CHECK-ARM64-EABI-MEABI-GNU: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01_mcount"{{.*}} }
+// CHECK-ARM64-EABI-NOT: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01__gnu_mcount_nc"{{.*}} }
+// CHECK-ARM-EABI-FREEBSD: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="__mcount"{{.*}} }
+// CHECK-ARM-EABI-FREEBSD-NOT: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01__gnu_mcount_nc"{{.*}} }
+// CHECK-ARM64-EABI-FREEBSD: attributes #{{[0-9]+}} = { {{.*}}"counting-function"=".mcount"{{.*}} }
+// CHECK-ARM64-EABI-FREEBSD-NOT: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01__gnu_mcount_nc"{{.*}} }
+// CHECK-ARM-EABI-NETBSD: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="_mcount"{{.*}} }
+// CHECK-ARM-EABI-NETBSD-NOT: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01__gnu_mcount_nc"{{.*}} }
+// CHECK-ARM-EABI-OPENBSD: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="__mcount"{{.*}} }
+// CHECK-ARM-EABI-OPENBSD-NOT: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01__gnu_mcount_nc"{{.*}} }
+// CHECK-ARM64-EABI-OPENBSD: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="mcount"{{.*}} }
+// CHECK-ARM64-EABI-OPENBSD-NOT: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01__gnu_mcount_nc"{{.*}} }
+// CHECK-ARM-EABI-MEABI-GNU-NOT: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="mcount"{{.*}} }
+// CHECK-ARM-EABI-MEABI-GNU: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01__gnu_mcount_nc"{{.*}} }
+// CHECK-ARM-EABI-BITRIG: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="__mcount"{{.*}} }
+// CHECK-ARM-EABI-BITRIG-NOT: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01__gnu_mcount_nc"{{.*}} }
+// CHECK-ARM54-EABI-BITRIG: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="mcount"{{.*}} }
+// CHECK-ARM54-EABI-BITRIG-NOT: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01__gnu_mcount_nc"{{.*}} }
+// CHECK-ARM-EABI-RTEMS: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="mcount"{{.*}} }
+// CHECK-ARM-EABI-RTEMS-NOT: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01__gnu_mcount_nc"{{.*}} }
+// CHECK-ARM64-EABI-RTEMS: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="mcount"{{.*}} }
+// CHECK-ARM64-EABI-RTEMS-NOT: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01__gnu_mcount_nc"{{.*}} }
+// CHECK-ARM-EABI-CLOUDABI: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="mcount"{{.*}} }
+// CHECK-ARM-EABI-CLOUDABI-NOT: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01__gnu_mcount_nc"{{.*}} }
+// CHECK-ARM64-EABI-CLOUDABI: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="mcount"{{.*}} }
+// CHECK-ARM64-EABI-CLOUDABI-NOT: attributes #{{[0-9]+}} = { {{.*}}"counting-function"="\01__gnu_mcount_nc"{{.*}} }
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