[libc-commits] [libc] [libc][math] Update getpayload and fmul with NaN inputs. (PR #99812)
via libc-commits
libc-commits at lists.llvm.org
Sun Jul 21 14:43:25 PDT 2024
https://github.com/lntue updated https://github.com/llvm/llvm-project/pull/99812
>From 2c7d580f7d84ae54d971499b681e9fe05fc06928 Mon Sep 17 00:00:00 2001
From: Tue Ly <lntue.h at gmail.com>
Date: Sun, 21 Jul 2024 15:55:26 +0000
Subject: [PATCH 1/2] [libc][math] Update getpayload and fmul with NaN inputs.
---
libc/src/__support/FPUtil/BasicOperations.h | 7 ++-
libc/src/__support/FPUtil/CMakeLists.txt | 57 +++++++++++----------
libc/src/__support/FPUtil/generic/mul.h | 20 ++++----
libc/test/src/math/smoke/MulTest.h | 19 +------
4 files changed, 46 insertions(+), 57 deletions(-)
diff --git a/libc/src/__support/FPUtil/BasicOperations.h b/libc/src/__support/FPUtil/BasicOperations.h
index a963a92bfb074..40f37b281b02c 100644
--- a/libc/src/__support/FPUtil/BasicOperations.h
+++ b/libc/src/__support/FPUtil/BasicOperations.h
@@ -11,8 +11,8 @@
#include "FEnvImpl.h"
#include "FPBits.h"
+#include "dyadic_float.h"
-#include "FEnvImpl.h"
#include "src/__support/CPP/type_traits.h"
#include "src/__support/common.h"
#include "src/__support/macros/config.h"
@@ -274,7 +274,10 @@ LIBC_INLINE cpp::enable_if_t<cpp::is_floating_point_v<T>, T> getpayload(T x) {
if (!x_bits.is_nan())
return T(-1.0);
- return T(x_bits.uintval() & (FPBits::FRACTION_MASK >> 1));
+ DyadicFloat<FPBits::STORAGE_LEN> payload(
+ Sign::POS, 0, x_bits.uintval() & (FPBits::FRACTION_MASK >> 1));
+
+ return static_cast<T>(payload);
}
template <bool IsSignaling, typename T>
diff --git a/libc/src/__support/FPUtil/CMakeLists.txt b/libc/src/__support/FPUtil/CMakeLists.txt
index 793d3a121c742..8804f3a4d5e23 100644
--- a/libc/src/__support/FPUtil/CMakeLists.txt
+++ b/libc/src/__support/FPUtil/CMakeLists.txt
@@ -75,19 +75,6 @@ add_header_library(
libc.src.__support.common
)
-add_header_library(
- basic_operations
- HDRS
- BasicOperations.h
- DEPENDS
- .fp_bits
- .fenv_impl
- libc.src.__support.CPP.type_traits
- libc.src.__support.uint128
- libc.src.__support.common
- libc.src.__support.macros.optimization
-)
-
add_header_library(
division_and_remainder_operations
HDRS
@@ -113,21 +100,6 @@ add_header_library(
)
-add_header_library(
- hypot
- HDRS
- Hypot.h
- DEPENDS
- .basic_operations
- .fenv_impl
- .fp_bits
- .rounding_mode
- libc.src.__support.common
- libc.src.__support.CPP.bit
- libc.src.__support.CPP.type_traits
- libc.src.__support.uint128
-)
-
add_header_library(
sqrt
HDRS
@@ -208,6 +180,35 @@ add_header_library(
libc.src.__support.macros.optimization
)
+add_header_library(
+ basic_operations
+ HDRS
+ BasicOperations.h
+ DEPENDS
+ .dyadic_float
+ .fp_bits
+ .fenv_impl
+ libc.src.__support.CPP.type_traits
+ libc.src.__support.uint128
+ libc.src.__support.common
+ libc.src.__support.macros.optimization
+)
+
+add_header_library(
+ hypot
+ HDRS
+ Hypot.h
+ DEPENDS
+ .basic_operations
+ .fenv_impl
+ .fp_bits
+ .rounding_mode
+ libc.src.__support.common
+ libc.src.__support.CPP.bit
+ libc.src.__support.CPP.type_traits
+ libc.src.__support.uint128
+)
+
add_header_library(
manipulation_functions
HDRS
diff --git a/libc/src/__support/FPUtil/generic/mul.h b/libc/src/__support/FPUtil/generic/mul.h
index 02fc69c6cb1ba..61be3719e123a 100644
--- a/libc/src/__support/FPUtil/generic/mul.h
+++ b/libc/src/__support/FPUtil/generic/mul.h
@@ -50,19 +50,19 @@ mul(InType x, InType y) {
raise_except_if_required(FE_INVALID);
if (x_bits.is_quiet_nan()) {
- InStorageType x_payload = static_cast<InStorageType>(getpayload(x));
- if ((x_payload & ~(OutFPBits::FRACTION_MASK >> 1)) == 0)
- return OutFPBits::quiet_nan(x_bits.sign(),
- static_cast<OutStorageType>(x_payload))
- .get_val();
+ InStorageType x_payload = x_bits.get_mantissa();
+ x_payload >>= (InFPBits::FRACTION_LEN - OutFPBits::FRACTION_LEN);
+ return OutFPBits::quiet_nan(x_bits.sign(),
+ static_cast<OutStorageType>(x_payload))
+ .get_val();
}
if (y_bits.is_quiet_nan()) {
- InStorageType y_payload = static_cast<InStorageType>(getpayload(y));
- if ((y_payload & ~(OutFPBits::FRACTION_MASK >> 1)) == 0)
- return OutFPBits::quiet_nan(y_bits.sign(),
- static_cast<OutStorageType>(y_payload))
- .get_val();
+ InStorageType y_payload = y_bits.get_mantissa();
+ y_payload >>= (InFPBits::FRACTION_LEN - OutFPBits::FRACTION_LEN);
+ return OutFPBits::quiet_nan(y_bits.sign(),
+ static_cast<OutStorageType>(y_payload))
+ .get_val();
}
return OutFPBits::quiet_nan().get_val();
diff --git a/libc/test/src/math/smoke/MulTest.h b/libc/test/src/math/smoke/MulTest.h
index e2298eaeeb216..0c847e39687b7 100644
--- a/libc/test/src/math/smoke/MulTest.h
+++ b/libc/test/src/math/smoke/MulTest.h
@@ -38,23 +38,8 @@ class MulTest : public LIBC_NAMESPACE::testing::FEnvSafeTest {
EXPECT_FP_IS_NAN_WITH_EXCEPTION(func(sNaN, sNaN), FE_INVALID);
InType qnan_42 = InFPBits::quiet_nan(Sign::POS, 0x42).get_val();
- EXPECT_FP_EQ(InType(0x42.0p+0),
- LIBC_NAMESPACE::fputil::getpayload(func(qnan_42, zero)));
- EXPECT_FP_EQ(InType(0x42.0p+0),
- LIBC_NAMESPACE::fputil::getpayload(func(zero, qnan_42)));
-
- if constexpr (sizeof(OutType) < sizeof(InType)) {
- InStorageType max_payload = InFPBits::FRACTION_MASK >> 1;
- InType qnan_max = InFPBits::quiet_nan(Sign::POS, max_payload).get_val();
- EXPECT_FP_EQ(zero,
- LIBC_NAMESPACE::fputil::getpayload(func(qnan_max, zero)));
- EXPECT_FP_EQ(zero,
- LIBC_NAMESPACE::fputil::getpayload(func(zero, qnan_max)));
- EXPECT_FP_EQ(InType(0x42.0p+0),
- LIBC_NAMESPACE::fputil::getpayload(func(qnan_max, qnan_42)));
- EXPECT_FP_EQ(InType(0x42.0p+0),
- LIBC_NAMESPACE::fputil::getpayload(func(qnan_42, qnan_max)));
- }
+ EXPECT_FP_IS_NAN(func(qnan_42, zero));
+ EXPECT_FP_IS_NAN(func(zero, qnan_42));
EXPECT_FP_EQ(inf, func(inf, InType(1.0)));
EXPECT_FP_EQ(neg_inf, func(neg_inf, InType(1.0)));
>From 36e7ca40049922fe7e77275b16f75b423d07332a Mon Sep 17 00:00:00 2001
From: Tue Ly <lntue.h at gmail.com>
Date: Sun, 21 Jul 2024 21:42:38 +0000
Subject: [PATCH 2/2] Address comments and fix the same issue for add_sub, div,
and FMA.
---
libc/src/__support/FPUtil/BasicOperations.h | 12 ++++--
libc/src/__support/FPUtil/generic/FMA.h | 43 ++++++++++++---------
libc/src/__support/FPUtil/generic/add_sub.h | 26 +++++++------
libc/src/__support/FPUtil/generic/div.h | 20 +++++-----
libc/src/__support/FPUtil/generic/mul.h | 4 +-
5 files changed, 60 insertions(+), 45 deletions(-)
diff --git a/libc/src/__support/FPUtil/BasicOperations.h b/libc/src/__support/FPUtil/BasicOperations.h
index 40f37b281b02c..3b7d7a5c249ae 100644
--- a/libc/src/__support/FPUtil/BasicOperations.h
+++ b/libc/src/__support/FPUtil/BasicOperations.h
@@ -269,15 +269,21 @@ totalordermag(T x, T y) {
template <typename T>
LIBC_INLINE cpp::enable_if_t<cpp::is_floating_point_v<T>, T> getpayload(T x) {
using FPBits = FPBits<T>;
+ using StorageType = typename FPBits::StorageType;
FPBits x_bits(x);
if (!x_bits.is_nan())
return T(-1.0);
- DyadicFloat<FPBits::STORAGE_LEN> payload(
- Sign::POS, 0, x_bits.uintval() & (FPBits::FRACTION_MASK >> 1));
+ StorageType payload = x_bits.uintval() & (FPBits::FRACTION_MASK >> 1);
+
+ if constexpr (is_big_int_v<StorageType>) {
+ DyadicFloat<FPBits::STORAGE_LEN> payload_dfloat(Sign::POS, 0, payload);
- return static_cast<T>(payload);
+ return static_cast<T>(payload_dfloat);
+ } else {
+ return static_cast<T>(payload);
+ }
}
template <bool IsSignaling, typename T>
diff --git a/libc/src/__support/FPUtil/generic/FMA.h b/libc/src/__support/FPUtil/generic/FMA.h
index 337301d86d919..87806b20f8cfa 100644
--- a/libc/src/__support/FPUtil/generic/FMA.h
+++ b/libc/src/__support/FPUtil/generic/FMA.h
@@ -129,27 +129,27 @@ fma(InType x, InType y, InType z) {
raise_except_if_required(FE_INVALID);
if (x_bits.is_quiet_nan()) {
- InStorageType x_payload = static_cast<InStorageType>(getpayload(x));
- if ((x_payload & ~(OutFPBits::FRACTION_MASK >> 1)) == 0)
- return OutFPBits::quiet_nan(x_bits.sign(),
- static_cast<OutStorageType>(x_payload))
- .get_val();
+ InStorageType x_payload = x_bits.get_mantissa();
+ x_payload >>= InFPBits::FRACTION_LEN - OutFPBits::FRACTION_LEN;
+ return OutFPBits::quiet_nan(x_bits.sign(),
+ static_cast<OutStorageType>(x_payload))
+ .get_val();
}
if (y_bits.is_quiet_nan()) {
- InStorageType y_payload = static_cast<InStorageType>(getpayload(y));
- if ((y_payload & ~(OutFPBits::FRACTION_MASK >> 1)) == 0)
- return OutFPBits::quiet_nan(y_bits.sign(),
- static_cast<OutStorageType>(y_payload))
- .get_val();
+ InStorageType y_payload = y_bits.get_mantissa();
+ y_payload >>= InFPBits::FRACTION_LEN - OutFPBits::FRACTION_LEN;
+ return OutFPBits::quiet_nan(y_bits.sign(),
+ static_cast<OutStorageType>(y_payload))
+ .get_val();
}
if (z_bits.is_quiet_nan()) {
- InStorageType z_payload = static_cast<InStorageType>(getpayload(z));
- if ((z_payload & ~(OutFPBits::FRACTION_MASK >> 1)) == 0)
- return OutFPBits::quiet_nan(z_bits.sign(),
- static_cast<OutStorageType>(z_payload))
- .get_val();
+ InStorageType z_payload = z_bits.get_mantissa();
+ z_payload >>= InFPBits::FRACTION_LEN - OutFPBits::FRACTION_LEN;
+ return OutFPBits::quiet_nan(z_bits.sign(),
+ static_cast<OutStorageType>(z_payload))
+ .get_val();
}
return OutFPBits::quiet_nan().get_val();
@@ -163,18 +163,25 @@ fma(InType x, InType y, InType z) {
int y_exp = 0;
int z_exp = 0;
+ // Denormal scaling = 2^(fraction length).
+ constexpr InType DENORMAL_SCALING =
+ InFPBits(static_cast<InStorageType>(InFPBits::FRACTION_LEN +
+ InFPBits::EXP_BIAS)
+ << InFPBits::SIG_LEN)
+ .get_val();
+
// Normalize denormal inputs.
if (LIBC_UNLIKELY(InFPBits(x).is_subnormal())) {
x_exp -= InFPBits::FRACTION_LEN;
- x *= InType(InStorageType(1) << InFPBits::FRACTION_LEN);
+ x *= DENORMAL_SCALING;
}
if (LIBC_UNLIKELY(InFPBits(y).is_subnormal())) {
y_exp -= InFPBits::FRACTION_LEN;
- y *= InType(InStorageType(1) << InFPBits::FRACTION_LEN);
+ y *= DENORMAL_SCALING;
}
if (LIBC_UNLIKELY(InFPBits(z).is_subnormal())) {
z_exp -= InFPBits::FRACTION_LEN;
- z *= InType(InStorageType(1) << InFPBits::FRACTION_LEN);
+ z *= DENORMAL_SCALING;
}
x_bits = InFPBits(x);
diff --git a/libc/src/__support/FPUtil/generic/add_sub.h b/libc/src/__support/FPUtil/generic/add_sub.h
index ec20a8723b704..850db3f83209e 100644
--- a/libc/src/__support/FPUtil/generic/add_sub.h
+++ b/libc/src/__support/FPUtil/generic/add_sub.h
@@ -56,19 +56,19 @@ add_or_sub(InType x, InType y) {
raise_except_if_required(FE_INVALID);
if (x_bits.is_quiet_nan()) {
- InStorageType x_payload = static_cast<InStorageType>(getpayload(x));
- if ((x_payload & ~(OutFPBits::FRACTION_MASK >> 1)) == 0)
- return OutFPBits::quiet_nan(x_bits.sign(),
- static_cast<OutStorageType>(x_payload))
- .get_val();
+ InStorageType x_payload = x_bits.get_mantissa();
+ x_payload >>= InFPBits::FRACTION_LEN - OutFPBits::FRACTION_LEN;
+ return OutFPBits::quiet_nan(x_bits.sign(),
+ static_cast<OutStorageType>(x_payload))
+ .get_val();
}
if (y_bits.is_quiet_nan()) {
- InStorageType y_payload = static_cast<InStorageType>(getpayload(y));
- if ((y_payload & ~(OutFPBits::FRACTION_MASK >> 1)) == 0)
- return OutFPBits::quiet_nan(y_bits.sign(),
- static_cast<OutStorageType>(y_payload))
- .get_val();
+ InStorageType y_payload = y_bits.get_mantissa();
+ y_payload >>= InFPBits::FRACTION_LEN - OutFPBits::FRACTION_LEN;
+ return OutFPBits::quiet_nan(y_bits.sign(),
+ static_cast<OutStorageType>(y_payload))
+ .get_val();
}
return OutFPBits::quiet_nan().get_val();
@@ -174,10 +174,12 @@ add_or_sub(InType x, InType y) {
else
aligned_min_mant_sticky = true;
+ InStorageType min_mant_sticky(static_cast<int>(aligned_min_mant_sticky));
+
if (is_effectively_add)
- result_mant = max_mant + (aligned_min_mant | aligned_min_mant_sticky);
+ result_mant = max_mant + (aligned_min_mant | min_mant_sticky);
else
- result_mant = max_mant - (aligned_min_mant | aligned_min_mant_sticky);
+ result_mant = max_mant - (aligned_min_mant | min_mant_sticky);
}
int result_exp = max_bits.get_exponent() - RESULT_FRACTION_LEN;
diff --git a/libc/src/__support/FPUtil/generic/div.h b/libc/src/__support/FPUtil/generic/div.h
index 27545786aea17..dad1772fce750 100644
--- a/libc/src/__support/FPUtil/generic/div.h
+++ b/libc/src/__support/FPUtil/generic/div.h
@@ -49,19 +49,19 @@ div(InType x, InType y) {
raise_except_if_required(FE_INVALID);
if (x_bits.is_quiet_nan()) {
- InStorageType x_payload = static_cast<InStorageType>(getpayload(x));
- if ((x_payload & ~(OutFPBits::FRACTION_MASK >> 1)) == 0)
- return OutFPBits::quiet_nan(x_bits.sign(),
- static_cast<OutStorageType>(x_payload))
- .get_val();
+ InStorageType x_payload = x_bits.get_mantissa();
+ x_payload >>= InFPBits::FRACTION_LEN - OutFPBits::FRACTION_LEN;
+ return OutFPBits::quiet_nan(x_bits.sign(),
+ static_cast<OutStorageType>(x_payload))
+ .get_val();
}
if (y_bits.is_quiet_nan()) {
- InStorageType y_payload = static_cast<InStorageType>(getpayload(y));
- if ((y_payload & ~(OutFPBits::FRACTION_MASK >> 1)) == 0)
- return OutFPBits::quiet_nan(y_bits.sign(),
- static_cast<OutStorageType>(y_payload))
- .get_val();
+ InStorageType y_payload = y_bits.get_mantissa();
+ y_payload >>= InFPBits::FRACTION_LEN - OutFPBits::FRACTION_LEN;
+ return OutFPBits::quiet_nan(y_bits.sign(),
+ static_cast<OutStorageType>(y_payload))
+ .get_val();
}
return OutFPBits::quiet_nan().get_val();
diff --git a/libc/src/__support/FPUtil/generic/mul.h b/libc/src/__support/FPUtil/generic/mul.h
index 61be3719e123a..20d9a77792762 100644
--- a/libc/src/__support/FPUtil/generic/mul.h
+++ b/libc/src/__support/FPUtil/generic/mul.h
@@ -51,7 +51,7 @@ mul(InType x, InType y) {
if (x_bits.is_quiet_nan()) {
InStorageType x_payload = x_bits.get_mantissa();
- x_payload >>= (InFPBits::FRACTION_LEN - OutFPBits::FRACTION_LEN);
+ x_payload >>= InFPBits::FRACTION_LEN - OutFPBits::FRACTION_LEN;
return OutFPBits::quiet_nan(x_bits.sign(),
static_cast<OutStorageType>(x_payload))
.get_val();
@@ -59,7 +59,7 @@ mul(InType x, InType y) {
if (y_bits.is_quiet_nan()) {
InStorageType y_payload = y_bits.get_mantissa();
- y_payload >>= (InFPBits::FRACTION_LEN - OutFPBits::FRACTION_LEN);
+ y_payload >>= InFPBits::FRACTION_LEN - OutFPBits::FRACTION_LEN;
return OutFPBits::quiet_nan(y_bits.sign(),
static_cast<OutStorageType>(y_payload))
.get_val();
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