[llvm-commits] [llvm] r125442 - in /llvm/trunk: lib/Transforms/Scalar/SimplifyLibCalls.cpp test/Transforms/SimplifyLibCalls/Printf.ll
Daniel Dunbar
daniel at zuster.org
Sat Feb 12 10:19:57 PST 2011
Author: ddunbar
Date: Sat Feb 12 12:19:57 2011
New Revision: 125442
URL: http://llvm.org/viewvc/llvm-project?rev=125442&view=rev
Log:
SimplifyLibCalls: Add missing legalize check on various printf to puts and
putchar transforms, their return values are not compatible.
Modified:
llvm/trunk/lib/Transforms/Scalar/SimplifyLibCalls.cpp
llvm/trunk/test/Transforms/SimplifyLibCalls/Printf.ll
Modified: llvm/trunk/lib/Transforms/Scalar/SimplifyLibCalls.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/SimplifyLibCalls.cpp?rev=125442&r1=125441&r2=125442&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/SimplifyLibCalls.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/SimplifyLibCalls.cpp Sat Feb 12 12:19:57 2011
@@ -1092,8 +1092,13 @@
return CI->use_empty() ? (Value*)CI :
ConstantInt::get(CI->getType(), 0);
- // printf("x") -> putchar('x'), even for '%'. Return the result of putchar
- // in case there is an error writing to stdout.
+ // Do not do any of the following transformations if the printf return value
+ // is used, in general the printf return value is not compatible with either
+ // putchar() or puts().
+ if (!CI->use_empty())
+ return 0;
+
+ // printf("x") -> putchar('x'), even for '%'.
if (FormatStr.size() == 1) {
Value *Res = EmitPutChar(B.getInt32(FormatStr[0]), B, TD);
if (CI->use_empty()) return CI;
@@ -1126,8 +1131,7 @@
// printf("%s\n", str) --> puts(str)
if (FormatStr == "%s\n" && CI->getNumArgOperands() > 1 &&
- CI->getArgOperand(1)->getType()->isPointerTy() &&
- CI->use_empty()) {
+ CI->getArgOperand(1)->getType()->isPointerTy()) {
EmitPutS(CI->getArgOperand(1), B, TD);
return CI;
}
@@ -1344,7 +1348,7 @@
if (!GetConstantStringInfo(CI->getArgOperand(0), Str))
return 0;
- if (Str.empty()) {
+ if (Str.empty() && CI->use_empty()) {
// puts("") -> putchar('\n')
Value *Res = EmitPutChar(B.getInt32('\n'), B, TD);
if (CI->use_empty()) return CI;
Modified: llvm/trunk/test/Transforms/SimplifyLibCalls/Printf.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SimplifyLibCalls/Printf.ll?rev=125442&r1=125441&r2=125442&view=diff
==============================================================================
--- llvm/trunk/test/Transforms/SimplifyLibCalls/Printf.ll (original)
+++ llvm/trunk/test/Transforms/SimplifyLibCalls/Printf.ll Sat Feb 12 12:19:57 2011
@@ -1,23 +1,36 @@
; RUN: opt < %s -simplify-libcalls -S -o %t
; RUN: FileCheck < %t %s
-; CHECK-NOT: call{{.*}}printf
-; CHECK: putchar
-
@str = internal constant [13 x i8] c"hello world\0A\00" ; <[13 x i8]*> [#uses=1]
@str1 = internal constant [2 x i8] c"h\00" ; <[2 x i8]*> [#uses=1]
-define void @foo() {
+declare i32 @printf(i8*, ...)
+
+; CHECK: define void @f0
+; CHECK-NOT: printf
+; CHECK: }
+define void @f0() {
entry:
%tmp1 = tail call i32 (i8*, ...)* @printf( i8* getelementptr ([13 x i8]* @str, i32 0, i32 0) ) ; <i32> [#uses=0]
ret void
}
-declare i32 @printf(i8*, ...)
-
-define void @bar() {
+; CHECK: define void @f1
+; CHECK-NOT: printf
+; CHECK: }
+define void @f1() {
entry:
%tmp1 = tail call i32 (i8*, ...)* @printf( i8* getelementptr ([2 x i8]* @str1, i32 0, i32 0) ) ; <i32> [#uses=0]
ret void
}
+; Verify that we don't turn this into a putchar call (thus changing the return
+; value).
+;
+; CHECK: define i32 @f2
+; CHECK: printf
+; CHECK: }
+define i32 @f2() {
+ %call = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([2 x i8]* @str1, i32 0, i32 0))
+ ret i32 %call
+}
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