[libc-commits] [libc] 5df182f - [libc] disable printf Lf tests for float128 plats

[Michael Jones via libc-commits]

Author: Michael Jones
Date: 2023-06-08T14:35:51-07:00
New Revision: 5df182f121ce483ba9050cd8e7c9c9a48757b1e5

URL: https://github.com/llvm/llvm-project/commit/5df182f121ce483ba9050cd8e7c9c9a48757b1e5
DIFF: https://github.com/llvm/llvm-project/commit/5df182f121ce483ba9050cd8e7c9c9a48757b1e5.diff

LOG: [libc] disable printf Lf tests for float128 plats

The results for the %Lf tests were calculated on 80 bit long double
systems, meaning the results are not necessarily accurate for float128
systems. In future these will be fixed, but for the moment I'm just
turning them off.

Differential Revision: https://reviews.llvm.org/D152471

Added: 
    

Modified: 
    libc/test/src/stdio/sprintf_test.cpp

Removed: 
    


################################################################################
diff  --git a/libc/test/src/stdio/sprintf_test.cpp b/libc/test/src/stdio/sprintf_test.cpp
index e6628eecd8289..9fb7705334046 100644
--- a/libc/test/src/stdio/sprintf_test.cpp
+++ b/libc/test/src/stdio/sprintf_test.cpp
@@ -928,12 +928,16 @@ TEST_F(LlvmLibcSPrintfTest, FloatDecimalConv) {
 
   // Length Modifier Tests.
 
-  // TODO: Fix long doubles (needs bigger table or alternate algorithm.)
-  // Currently the table values are generated, which is very slow.
+  // TODO(michaelrj): Add tests for LONG_DOUBLE_IS_DOUBLE and 128 bit long
+  // double systems.
+  // TODO(michaelrj): Fix the tests to only depend on the digits the long double
+  // is accurate for.
 
   written = __llvm_libc::sprintf(buff, "%Lf", 1.0L);
   ASSERT_STREQ_LEN(written, buff, "1.000000");
 
+#if defined(SPECIAL_X86_LONG_DOUBLE)
+
   written = __llvm_libc::sprintf(buff, "%Lf", 1e100L);
   ASSERT_STREQ_LEN(written, buff,
                    "99999999999999999996693535322073426194986990198284960792713"
@@ -941,8 +945,6 @@ TEST_F(LlvmLibcSPrintfTest, FloatDecimalConv) {
 
   char big_buff[10000];
 
-  // written = __llvm_libc::sprintf(big_buff, "%Lf", 0x1p16383L);
-
   written = __llvm_libc::sprintf(big_buff, "%Lf", 1e1000L);
   ASSERT_STREQ_LEN(
       written, big_buff,
@@ -1035,10 +1037,8 @@ TEST_F(LlvmLibcSPrintfTest, FloatDecimalConv) {
       "231934194956788626761834746430104077432547436359522462253411168467463134"
       "24896.000000");
 
-
   written = __llvm_libc::sprintf(big_buff, "%.10Lf", 1e-10L);
-  ASSERT_STREQ_LEN(
-      written, big_buff, "0.0000000001");
+  ASSERT_STREQ_LEN(written, big_buff, "0.0000000001");
 
   written = __llvm_libc::sprintf(big_buff, "%.7500Lf", 1e-4900L);
   ASSERT_STREQ_LEN(
@@ -1149,6 +1149,7 @@ TEST_F(LlvmLibcSPrintfTest, FloatDecimalConv) {
       "570449525088342437216896462077260223998756027453411520977536701491759878"
       "422771447006016890777855573925295187921971811871399320142563330377888532"
       "179817332113");
+#endif // SPECIAL_X86_LONG_DOUBLE
 
   /*
     written = __llvm_libc::sprintf(buff, "%La", 0.1L);