Remove any 'nest' parameter attributes if the function

is not passed as an argument to a trampoline intrinsic.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47220 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Duncan Sands 2008-02-16 20:56:04 +00:00
parent b3a94608b3
commit 3d5378ff8e
2 changed files with 109 additions and 10 deletions

View File

@ -21,6 +21,7 @@
#include "llvm/Instructions.h"
#include "llvm/IntrinsicInst.h"
#include "llvm/Module.h"
#include "llvm/ParameterAttributes.h"
#include "llvm/Pass.h"
#include "llvm/Analysis/ConstantFolding.h"
#include "llvm/Target/TargetData.h"
@ -46,6 +47,7 @@ STATISTIC(NumLocalized , "Number of globals localized");
STATISTIC(NumShrunkToBool , "Number of global vars shrunk to booleans");
STATISTIC(NumFastCallFns , "Number of functions converted to fastcc");
STATISTIC(NumCtorsEvaluated, "Number of static ctors evaluated");
STATISTIC(NumNestRemoved , "Number of nest attributes removed");
namespace {
struct VISIBILITY_HIDDEN GlobalOpt : public ModulePass {
@ -1590,6 +1592,35 @@ static void ChangeCalleesToFastCall(Function *F) {
}
}
static const ParamAttrsList *StripNest(const ParamAttrsList *Attrs) {
if (Attrs) {
for (unsigned i = 0, e = Attrs->size(); i != e; ++i) {
uint16_t A = Attrs->getParamAttrsAtIndex(i);
if (A & ParamAttr::Nest) {
Attrs = ParamAttrsList::excludeAttrs(Attrs, Attrs->getParamIndex(i),
ParamAttr::Nest);
// There can be only one.
break;
}
}
}
return Attrs;
}
static void RemoveNestAttribute(Function *F) {
F->setParamAttrs(StripNest(F->getParamAttrs()));
for (Value::use_iterator UI = F->use_begin(), E = F->use_end(); UI != E;++UI){
Instruction *User = cast<Instruction>(*UI);
if (CallInst *CI = dyn_cast<CallInst>(User)) {
CI->setParamAttrs(StripNest(CI->getParamAttrs()));
} else {
InvokeInst *II = cast<InvokeInst>(User);
II->setParamAttrs(StripNest(II->getParamAttrs()));
}
}
}
bool GlobalOpt::OptimizeFunctions(Module &M) {
bool Changed = false;
// Optimize functions.
@ -1601,16 +1632,27 @@ bool GlobalOpt::OptimizeFunctions(Module &M) {
M.getFunctionList().erase(F);
Changed = true;
++NumFnDeleted;
} else if (F->hasInternalLinkage() &&
F->getCallingConv() == CallingConv::C && !F->isVarArg() &&
OnlyCalledDirectly(F)) {
// If this function has C calling conventions, is not a varargs
// function, and is only called directly, promote it to use the Fast
// calling convention.
F->setCallingConv(CallingConv::Fast);
ChangeCalleesToFastCall(F);
++NumFastCallFns;
Changed = true;
} else if (F->hasInternalLinkage()) {
if (F->getCallingConv() == CallingConv::C && !F->isVarArg() &&
OnlyCalledDirectly(F)) {
// If this function has C calling conventions, is not a varargs
// function, and is only called directly, promote it to use the Fast
// calling convention.
F->setCallingConv(CallingConv::Fast);
ChangeCalleesToFastCall(F);
++NumFastCallFns;
Changed = true;
}
if (F->getParamAttrs() &&
F->getParamAttrs()->hasAttrSomewhere(ParamAttr::Nest) &&
OnlyCalledDirectly(F)) {
// The function is not used by a trampoline intrinsic, so it is safe
// to remove the 'nest' attribute.
RemoveNestAttribute(F);
++NumNestRemoved;
Changed = true;
}
}
}
return Changed;

View File

@ -0,0 +1,57 @@
; RUN: llvm-as < %s | opt -globalopt | llvm-dis | grep { nest } | count 1
%struct.FRAME.nest = type { i32, i32 (i32)* }
%struct.__builtin_trampoline = type { [10 x i8] }
@.str = internal constant [7 x i8] c"%d %d\0A\00" ; <[7 x i8]*> [#uses=1]
define i32 @process(i32 (i32)* %func) nounwind {
entry:
%tmp2 = tail call i32 %func( i32 1 ) nounwind ; <i32> [#uses=1]
ret i32 %tmp2
}
define internal fastcc i32 @g.1478(%struct.FRAME.nest* nest %CHAIN.1, i32 %m) nounwind {
entry:
%tmp3 = getelementptr %struct.FRAME.nest* %CHAIN.1, i32 0, i32 0 ; <i32*> [#uses=1]
%tmp4 = load i32* %tmp3, align 4 ; <i32> [#uses=1]
%tmp7 = icmp eq i32 %tmp4, %m ; <i1> [#uses=1]
%tmp78 = zext i1 %tmp7 to i32 ; <i32> [#uses=1]
ret i32 %tmp78
}
define internal i32 @f.1481(%struct.FRAME.nest* nest %CHAIN.2, i32 %m) nounwind {
entry:
%tmp4 = tail call fastcc i32 @g.1478( %struct.FRAME.nest* nest %CHAIN.2, i32 %m ) nounwind ; <i32> [#uses=1]
%tmp6 = getelementptr %struct.FRAME.nest* %CHAIN.2, i32 0, i32 0 ; <i32*> [#uses=1]
%tmp7 = load i32* %tmp6, align 4 ; <i32> [#uses=1]
%tmp9 = icmp eq i32 %tmp4, %tmp7 ; <i1> [#uses=1]
%tmp910 = zext i1 %tmp9 to i32 ; <i32> [#uses=1]
ret i32 %tmp910
}
define i32 @nest(i32 %n) nounwind {
entry:
%TRAMP.316 = alloca [10 x i8] ; <[10 x i8]*> [#uses=1]
%FRAME.0 = alloca %struct.FRAME.nest ; <%struct.FRAME.nest*> [#uses=3]
%TRAMP.316.sub = getelementptr [10 x i8]* %TRAMP.316, i32 0, i32 0 ; <i8*> [#uses=1]
%tmp3 = getelementptr %struct.FRAME.nest* %FRAME.0, i32 0, i32 0 ; <i32*> [#uses=1]
store i32 %n, i32* %tmp3, align 8
%FRAME.06 = bitcast %struct.FRAME.nest* %FRAME.0 to i8* ; <i8*> [#uses=1]
%tramp = call i8* @llvm.init.trampoline( i8* %TRAMP.316.sub, i8* bitcast (i32 (%struct.FRAME.nest*, i32)* @f.1481 to i8*), i8* %FRAME.06 ) ; <i8*> [#uses=1]
%tmp7 = getelementptr %struct.FRAME.nest* %FRAME.0, i32 0, i32 1 ; <i32 (i32)**> [#uses=1]
%tmp89 = bitcast i8* %tramp to i32 (i32)* ; <i32 (i32)*> [#uses=2]
store i32 (i32)* %tmp89, i32 (i32)** %tmp7, align 4
%tmp13 = call i32 @process( i32 (i32)* %tmp89 ) nounwind ; <i32> [#uses=1]
ret i32 %tmp13
}
declare i8* @llvm.init.trampoline(i8*, i8*, i8*) nounwind
define i32 @main() nounwind {
entry:
%tmp = tail call i32 @nest( i32 2 ) nounwind ; <i32> [#uses=1]
%tmp1 = tail call i32 @nest( i32 1 ) nounwind ; <i32> [#uses=1]
%tmp3 = tail call i32 (i8*, ...)* @printf( i8* noalias getelementptr ([7 x i8]* @.str, i32 0, i32 0), i32 %tmp1, i32 %tmp ) nounwind ; <i32> [#uses=0]
ret i32 undef
}
declare i32 @printf(i8*, ...) nounwind