if (FormatStr.size() == 1 || FormatStr == "%%")
return emitPutChar(B.getInt32(FormatStr[0]), B, TLI);
- // printf("%s", "a") --> putchar('a')
+ // Try to remove call or emit putchar/puts.
if (FormatStr == "%s" && CI->getNumArgOperands() > 1) {
- StringRef ChrStr;
- if (!getConstantStringInfo(CI->getOperand(1), ChrStr))
+ StringRef OperandStr;
+ if (!getConstantStringInfo(CI->getOperand(1), OperandStr))
return nullptr;
- if (ChrStr.size() != 1)
- return nullptr;
- return emitPutChar(B.getInt32(ChrStr[0]), B, TLI);
+ // printf("%s", "") --> NOP
+ if (OperandStr.empty())
+ return (Value *)CI;
+ // printf("%s", "a") --> putchar('a')
+ if (OperandStr.size() == 1)
+ return emitPutChar(B.getInt32(OperandStr[0]), B, TLI);
+ // printf("%s", str"\n") --> puts(str)
+ if (OperandStr.back() == '\n') {
+ OperandStr = OperandStr.drop_back();
+ Value *GV = B.CreateGlobalString(OperandStr, "str");
+ return emitPutS(GV, B, TLI);
+ }
+ return nullptr;
}
// printf("foo\n") --> puts("foo")
; CHECK: @[[CHARSTR:[a-zA-Z0-9_$"\\.-]+]] = constant [2 x i8] c"a\00"
; CHECK: @[[EMPTY:[a-zA-Z0-9_$"\\.-]+]] = constant [1 x i8] zeroinitializer
; CHECK: @[[STR:[a-zA-Z0-9_$"\\.-]+]] = private unnamed_addr constant [12 x i8] c"hello world\00", align 1
+; CHECK: @[[STR_1:[a-zA-Z0-9_$"\\.-]+]] = private unnamed_addr constant [12 x i8] c"hello world\00", align 1
+; CHECK: @[[STR_2:[a-zA-Z0-9_$"\\.-]+]] = private unnamed_addr constant [12 x i8] c"hello world\00", align 1
;.
define void @test_simplify1() {
; CHECK-LABEL: @test_simplify1(
ret void
}
+; printf("%s", "") --> noop
+
define void @test_simplify8() {
; CHECK-LABEL: @test_simplify8(
-; CHECK-NEXT: call void (i8*, ...) @printf(i8* noundef nonnull dereferenceable(1) getelementptr inbounds ([3 x i8], [3 x i8]* @format_str, i32 0, i32 0), i8* getelementptr inbounds ([1 x i8], [1 x i8]* @empty, i32 0, i32 0))
; CHECK-NEXT: ret void
;
%fmt = getelementptr [3 x i8], [3 x i8]* @format_str, i32 0, i32 0
ret void
}
+; printf("%s", str"\n") --> puts(str)
+
define void @test_simplify9() {
; CHECK-LABEL: @test_simplify9(
-; CHECK-NEXT: call void (i8*, ...) @printf(i8* noundef nonnull dereferenceable(1) getelementptr inbounds ([3 x i8], [3 x i8]* @format_str, i32 0, i32 0), i8* getelementptr inbounds ([13 x i8], [13 x i8]* @hello_world, i32 0, i32 0))
+; CHECK-NEXT: [[PUTS:%.*]] = call i32 @puts(i8* nonnull dereferenceable(1) getelementptr inbounds ([12 x i8], [12 x i8]* @str.1, i32 0, i32 0))
; CHECK-NEXT: ret void
;
%fmt = getelementptr [3 x i8], [3 x i8]* @format_str, i32 0, i32 0
ret void
}
+; printf("%s", "", ...) --> noop
+; printf("%s", "a", ...) --> putchar('a')
+; printf("%s", str"\n", ...) --> puts(str)
+
define void @test_simplify10() {
; CHECK-LABEL: @test_simplify10(
-; CHECK-NEXT: call void (i8*, ...) @printf(i8* noundef nonnull dereferenceable(1) getelementptr inbounds ([3 x i8], [3 x i8]* @format_str, i32 0, i32 0), i8* getelementptr inbounds ([1 x i8], [1 x i8]* @empty, i32 0, i32 0), i32 42, double 0x40091EB860000000)
; CHECK-NEXT: [[PUTCHAR:%.*]] = call i32 @putchar(i32 97)
-; CHECK-NEXT: call void (i8*, ...) @printf(i8* noundef nonnull dereferenceable(1) getelementptr inbounds ([3 x i8], [3 x i8]* @format_str, i32 0, i32 0), i8* getelementptr inbounds ([13 x i8], [13 x i8]* @hello_world, i32 0, i32 0), i32 42, double 0x40091EB860000000)
+; CHECK-NEXT: [[PUTS:%.*]] = call i32 @puts(i8* nonnull dereferenceable(1) getelementptr inbounds ([12 x i8], [12 x i8]* @str.2, i32 0, i32 0))
; CHECK-NEXT: ret void
;
%fmt = getelementptr [3 x i8], [3 x i8]* @format_str, i32 0, i32 0