mirror of
https://github.com/capstone-engine/llvm-capstone.git
synced 2024-10-11 05:15:50 +00:00
instcombine: Migrate strlen optimizations
This patch migrates the strlen optimizations from the simplify-libcalls pass into the instcombine library call simplifier. llvm-svn: 167103
This commit is contained in:
Meador Inge
parent
067294b3ac
commit
d589ac621b
@ -90,22 +90,6 @@ public:
|
||||
// Helper Functions
|
||||
//===----------------------------------------------------------------------===//
|
||||
|
||||
/// IsOnlyUsedInZeroEqualityComparison - Return true if it only matters that the
|
||||
/// value is equal or not-equal to zero.
|
||||
static bool IsOnlyUsedInZeroEqualityComparison(Value *V) {
|
||||
for (Value::use_iterator UI = V->use_begin(), E = V->use_end();
|
||||
UI != E; ++UI) {
|
||||
if (ICmpInst *IC = dyn_cast<ICmpInst>(*UI))
|
||||
if (IC->isEquality())
|
||||
if (Constant *C = dyn_cast<Constant>(IC->getOperand(1)))
|
||||
if (C->isNullValue())
|
||||
continue;
|
||||
// Unknown instruction.
|
||||
return false;
|
||||
}
|
||||
return true;
|
||||
}
|
||||
|
||||
static bool CallHasFloatingPointArgument(const CallInst *CI) {
|
||||
for (CallInst::const_op_iterator it = CI->op_begin(), e = CI->op_end();
|
||||
it != e; ++it) {
|
||||
@ -134,32 +118,6 @@ static bool IsOnlyUsedInEqualityComparison(Value *V, Value *With) {
|
||||
//===----------------------------------------------------------------------===//
|
||||
|
||||
namespace {
|
||||
//===---------------------------------------===//
|
||||
// 'strlen' Optimizations
|
||||
|
||||
struct StrLenOpt : public LibCallOptimization {
|
||||
virtual Value *CallOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
|
||||
FunctionType *FT = Callee->getFunctionType();
|
||||
if (FT->getNumParams() != 1 ||
|
||||
FT->getParamType(0) != B.getInt8PtrTy() ||
|
||||
!FT->getReturnType()->isIntegerTy())
|
||||
return 0;
|
||||
|
||||
Value *Src = CI->getArgOperand(0);
|
||||
|
||||
// Constant folding: strlen("xyz") -> 3
|
||||
if (uint64_t Len = GetStringLength(Src))
|
||||
return ConstantInt::get(CI->getType(), Len-1);
|
||||
|
||||
// strlen(x) != 0 --> *x != 0
|
||||
// strlen(x) == 0 --> *x == 0
|
||||
if (IsOnlyUsedInZeroEqualityComparison(CI))
|
||||
return B.CreateZExt(B.CreateLoad(Src, "strlenfirst"), CI->getType());
|
||||
return 0;
|
||||
}
|
||||
};
|
||||
|
||||
|
||||
//===---------------------------------------===//
|
||||
// 'strpbrk' Optimizations
|
||||
|
||||
@ -1146,7 +1104,7 @@ namespace {
|
||||
|
||||
StringMap<LibCallOptimization*> Optimizations;
|
||||
// String and Memory LibCall Optimizations
|
||||
StrLenOpt StrLen; StrPBrkOpt StrPBrk;
|
||||
StrPBrkOpt StrPBrk;
|
||||
StrToOpt StrTo; StrSpnOpt StrSpn; StrCSpnOpt StrCSpn; StrStrOpt StrStr;
|
||||
MemCmpOpt MemCmp; MemCpyOpt MemCpy; MemMoveOpt MemMove; MemSetOpt MemSet;
|
||||
// Math Library Optimizations
|
||||
@ -1215,7 +1173,6 @@ void SimplifyLibCalls::AddOpt(LibFunc::Func F1, LibFunc::Func F2,
|
||||
/// we know.
|
||||
void SimplifyLibCalls::InitOptimizations() {
|
||||
// String and Memory LibCall Optimizations
|
||||
Optimizations["strlen"] = &StrLen;
|
||||
Optimizations["strpbrk"] = &StrPBrk;
|
||||
Optimizations["strtol"] = &StrTo;
|
||||
Optimizations["strtod"] = &StrTo;
|
||||
|
||||
@ -63,6 +63,26 @@ public:
|
||||
}
|
||||
};
|
||||
|
||||
//===----------------------------------------------------------------------===//
|
||||
// Helper Functions
|
||||
//===----------------------------------------------------------------------===//
|
||||
|
||||
/// isOnlyUsedInZeroEqualityComparison - Return true if it only matters that the
|
||||
/// value is equal or not-equal to zero.
|
||||
static bool isOnlyUsedInZeroEqualityComparison(Value *V) {
|
||||
for (Value::use_iterator UI = V->use_begin(), E = V->use_end();
|
||||
UI != E; ++UI) {
|
||||
if (ICmpInst *IC = dyn_cast<ICmpInst>(*UI))
|
||||
if (IC->isEquality())
|
||||
if (Constant *C = dyn_cast<Constant>(IC->getOperand(1)))
|
||||
if (C->isNullValue())
|
||||
continue;
|
||||
// Unknown instruction.
|
||||
return false;
|
||||
}
|
||||
return true;
|
||||
}
|
||||
|
||||
//===----------------------------------------------------------------------===//
|
||||
// Fortified Library Call Optimizations
|
||||
//===----------------------------------------------------------------------===//
|
||||
@ -675,6 +695,28 @@ struct StrNCpyOpt : public LibCallOptimization {
|
||||
}
|
||||
};
|
||||
|
||||
struct StrLenOpt : public LibCallOptimization {
|
||||
virtual Value *callOptimizer(Function *Callee, CallInst *CI, IRBuilder<> &B) {
|
||||
FunctionType *FT = Callee->getFunctionType();
|
||||
if (FT->getNumParams() != 1 ||
|
||||
FT->getParamType(0) != B.getInt8PtrTy() ||
|
||||
!FT->getReturnType()->isIntegerTy())
|
||||
return 0;
|
||||
|
||||
Value *Src = CI->getArgOperand(0);
|
||||
|
||||
// Constant folding: strlen("xyz") -> 3
|
||||
if (uint64_t Len = GetStringLength(Src))
|
||||
return ConstantInt::get(CI->getType(), Len-1);
|
||||
|
||||
// strlen(x) != 0 --> *x != 0
|
||||
// strlen(x) == 0 --> *x == 0
|
||||
if (isOnlyUsedInZeroEqualityComparison(CI))
|
||||
return B.CreateZExt(B.CreateLoad(Src, "strlenfirst"), CI->getType());
|
||||
return 0;
|
||||
}
|
||||
};
|
||||
|
||||
} // End anonymous namespace.
|
||||
|
||||
namespace llvm {
|
||||
@ -702,6 +744,7 @@ class LibCallSimplifierImpl {
|
||||
StrCpyOpt StrCpy;
|
||||
StpCpyOpt StpCpy;
|
||||
StrNCpyOpt StrNCpy;
|
||||
StrLenOpt StrLen;
|
||||
|
||||
void initOptimizations();
|
||||
public:
|
||||
@ -733,6 +776,7 @@ void LibCallSimplifierImpl::initOptimizations() {
|
||||
Optimizations["strcpy"] = &StrCpy;
|
||||
Optimizations["stpcpy"] = &StpCpy;
|
||||
Optimizations["strncpy"] = &StrNCpy;
|
||||
Optimizations["strlen"] = &StrLen;
|
||||
}
|
||||
|
||||
Value *LibCallSimplifierImpl::optimizeCall(CallInst *CI) {
|
||||
|
||||
97
llvm/test/Transforms/InstCombine/strlen-1.ll
Normal file
97
llvm/test/Transforms/InstCombine/strlen-1.ll
Normal file
@ -0,0 +1,97 @@
|
||||
; Test that the strlen library call simplifier works correctly.
|
||||
;
|
||||
; RUN: opt < %s -instcombine -S | FileCheck %s
|
||||
|
||||
target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
|
||||
|
||||
@hello = constant [6 x i8] c"hello\00"
|
||||
@null = constant [1 x i8] zeroinitializer
|
||||
@null_hello = constant [7 x i8] c"\00hello\00"
|
||||
@nullstring = constant i8 0
|
||||
@a = common global [32 x i8] zeroinitializer, align 1
|
||||
|
||||
declare i32 @strlen(i8*)
|
||||
|
||||
; Check strlen(string constant) -> integer constant.
|
||||
|
||||
define i32 @test_simplify1() {
|
||||
; CHECK: @test_simplify1
|
||||
%hello_p = getelementptr [6 x i8]* @hello, i32 0, i32 0
|
||||
%hello_l = call i32 @strlen(i8* %hello_p)
|
||||
ret i32 %hello_l
|
||||
; CHECK-NEXT: ret i32 5
|
||||
}
|
||||
|
||||
define i32 @test_simplify2() {
|
||||
; CHECK: @test_simplify2
|
||||
%null_p = getelementptr [1 x i8]* @null, i32 0, i32 0
|
||||
%null_l = call i32 @strlen(i8* %null_p)
|
||||
ret i32 %null_l
|
||||
; CHECK-NEXT: ret i32 0
|
||||
}
|
||||
|
||||
define i32 @test_simplify3() {
|
||||
; CHECK: @test_simplify3
|
||||
%null_hello_p = getelementptr [7 x i8]* @null_hello, i32 0, i32 0
|
||||
%null_hello_l = call i32 @strlen(i8* %null_hello_p)
|
||||
ret i32 %null_hello_l
|
||||
; CHECK-NEXT: ret i32 0
|
||||
}
|
||||
|
||||
define i32 @test_simplify4() {
|
||||
; CHECK: @test_simplify4
|
||||
%len = tail call i32 @strlen(i8* @nullstring) nounwind
|
||||
ret i32 %len
|
||||
; CHECK-NEXT: ret i32 0
|
||||
}
|
||||
|
||||
; Check strlen(x) == 0 --> *x == 0.
|
||||
|
||||
define i1 @test_simplify5() {
|
||||
; CHECK: @test_simplify5
|
||||
%hello_p = getelementptr [6 x i8]* @hello, i32 0, i32 0
|
||||
%hello_l = call i32 @strlen(i8* %hello_p)
|
||||
%eq_hello = icmp eq i32 %hello_l, 0
|
||||
ret i1 %eq_hello
|
||||
; CHECK-NEXT: ret i1 false
|
||||
}
|
||||
|
||||
define i1 @test_simplify6() {
|
||||
; CHECK: @test_simplify6
|
||||
%null_p = getelementptr [1 x i8]* @null, i32 0, i32 0
|
||||
%null_l = call i32 @strlen(i8* %null_p)
|
||||
%eq_null = icmp eq i32 %null_l, 0
|
||||
ret i1 %eq_null
|
||||
; CHECK-NEXT: ret i1 true
|
||||
}
|
||||
|
||||
; Check strlen(x) != 0 --> *x != 0.
|
||||
|
||||
define i1 @test_simplify7() {
|
||||
; CHECK: @test_simplify7
|
||||
%hello_p = getelementptr [6 x i8]* @hello, i32 0, i32 0
|
||||
%hello_l = call i32 @strlen(i8* %hello_p)
|
||||
%ne_hello = icmp ne i32 %hello_l, 0
|
||||
ret i1 %ne_hello
|
||||
; CHECK-NEXT: ret i1 true
|
||||
}
|
||||
|
||||
define i1 @test_simplify8() {
|
||||
; CHECK: @test_simplify8
|
||||
%null_p = getelementptr [1 x i8]* @null, i32 0, i32 0
|
||||
%null_l = call i32 @strlen(i8* %null_p)
|
||||
%ne_null = icmp ne i32 %null_l, 0
|
||||
ret i1 %ne_null
|
||||
; CHECK-NEXT: ret i1 false
|
||||
}
|
||||
|
||||
; Check cases that shouldn't be simplified.
|
||||
|
||||
define i32 @test_no_simplify1() {
|
||||
; CHECK: @test_no_simplify1
|
||||
%a_p = getelementptr [32 x i8]* @a, i32 0, i32 0
|
||||
%a_l = call i32 @strlen(i8* %a_p)
|
||||
; CHECK-NEXT: %a_l = call i32 @strlen
|
||||
ret i32 %a_l
|
||||
; CHECK-NEXT: ret i32 %a_l
|
||||
}
|
||||
18
llvm/test/Transforms/InstCombine/strlen-2.ll
Normal file
18
llvm/test/Transforms/InstCombine/strlen-2.ll
Normal file
@ -0,0 +1,18 @@
|
||||
; Test that the strlen library call simplifier works correctly.
|
||||
;
|
||||
; RUN: opt < %s -instcombine -S | FileCheck %s
|
||||
|
||||
target datalayout = "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128"
|
||||
|
||||
@hello = constant [6 x i8] c"hello\00"
|
||||
|
||||
declare i32 @strlen(i8*, i32)
|
||||
|
||||
define i32 @test_no_simplify1() {
|
||||
; CHECK: @test_no_simplify1
|
||||
%hello_p = getelementptr [6 x i8]* @hello, i32 0, i32 0
|
||||
%hello_l = call i32 @strlen(i8* %hello_p, i32 187)
|
||||
; CHECK-NEXT: %hello_l = call i32 @strlen
|
||||
ret i32 %hello_l
|
||||
; CHECK-NEXT: ret i32 %hello_l
|
||||
}
|
||||
@ -1,62 +0,0 @@
|
||||
; Test that the StrCatOptimizer works correctly
|
||||
; RUN: opt < %s -simplify-libcalls -S | \
|
||||
; RUN: not grep "call.*strlen"
|
||||
|
||||
target datalayout = "e-p:32:32"
|
||||
@hello = constant [6 x i8] c"hello\00" ; <[6 x i8]*> [#uses=3]
|
||||
@null = constant [1 x i8] zeroinitializer ; <[1 x i8]*> [#uses=3]
|
||||
@null_hello = constant [7 x i8] c"\00hello\00" ; <[7 x i8]*> [#uses=1]
|
||||
@nullstring = constant i8 0
|
||||
|
||||
declare i32 @strlen(i8*)
|
||||
|
||||
define i32 @test1() {
|
||||
%hello_p = getelementptr [6 x i8]* @hello, i32 0, i32 0 ; <i8*> [#uses=1]
|
||||
%hello_l = call i32 @strlen( i8* %hello_p ) ; <i32> [#uses=1]
|
||||
ret i32 %hello_l
|
||||
}
|
||||
|
||||
define i32 @test2() {
|
||||
%null_p = getelementptr [1 x i8]* @null, i32 0, i32 0 ; <i8*> [#uses=1]
|
||||
%null_l = call i32 @strlen( i8* %null_p ) ; <i32> [#uses=1]
|
||||
ret i32 %null_l
|
||||
}
|
||||
|
||||
define i32 @test3() {
|
||||
%null_hello_p = getelementptr [7 x i8]* @null_hello, i32 0, i32 0 ; <i8*> [#uses=1]
|
||||
%null_hello_l = call i32 @strlen( i8* %null_hello_p ) ; <i32> [#uses=1]
|
||||
ret i32 %null_hello_l
|
||||
}
|
||||
|
||||
define i1 @test4() {
|
||||
%hello_p = getelementptr [6 x i8]* @hello, i32 0, i32 0 ; <i8*> [#uses=1]
|
||||
%hello_l = call i32 @strlen( i8* %hello_p ) ; <i32> [#uses=1]
|
||||
%eq_hello = icmp eq i32 %hello_l, 0 ; <i1> [#uses=1]
|
||||
ret i1 %eq_hello
|
||||
}
|
||||
|
||||
define i1 @test5() {
|
||||
%null_p = getelementptr [1 x i8]* @null, i32 0, i32 0 ; <i8*> [#uses=1]
|
||||
%null_l = call i32 @strlen( i8* %null_p ) ; <i32> [#uses=1]
|
||||
%eq_null = icmp eq i32 %null_l, 0 ; <i1> [#uses=1]
|
||||
ret i1 %eq_null
|
||||
}
|
||||
|
||||
define i1 @test6() {
|
||||
%hello_p = getelementptr [6 x i8]* @hello, i32 0, i32 0 ; <i8*> [#uses=1]
|
||||
%hello_l = call i32 @strlen( i8* %hello_p ) ; <i32> [#uses=1]
|
||||
%ne_hello = icmp ne i32 %hello_l, 0 ; <i1> [#uses=1]
|
||||
ret i1 %ne_hello
|
||||
}
|
||||
|
||||
define i1 @test7() {
|
||||
%null_p = getelementptr [1 x i8]* @null, i32 0, i32 0 ; <i8*> [#uses=1]
|
||||
%null_l = call i32 @strlen( i8* %null_p ) ; <i32> [#uses=1]
|
||||
%ne_null = icmp ne i32 %null_l, 0 ; <i1> [#uses=1]
|
||||
ret i1 %ne_null
|
||||
}
|
||||
|
||||
define i32 @test8() {
|
||||
%len = tail call i32 @strlen(i8* @nullstring) nounwind
|
||||
ret i32 %len
|
||||
}
|
||||
Loading…
Reference in New Issue
Block a user