[libc][math] Implement fast pass for double precision pow function with up to 1ULP error. (#101926)

Author: lntue

libc/config/darwin/arm/entrypoints.txt

@@ -227,6 +227,7 @@ set(TARGET_LIBM_ENTRYPOINTS
     libc.src.math.nexttoward
     libc.src.math.nexttowardf
     libc.src.math.nexttowardl
+    libc.src.math.pow
     libc.src.math.powf
     libc.src.math.remainderf
     libc.src.math.remainder

libc/config/linux/aarch64/entrypoints.txt

@@ -521,6 +521,7 @@ set(TARGET_LIBM_ENTRYPOINTS
     libc.src.math.nextup
     libc.src.math.nextupf
     libc.src.math.nextupl
+    libc.src.math.pow
     libc.src.math.powf
     libc.src.math.remainder
     libc.src.math.remainderf

libc/config/linux/arm/entrypoints.txt

@@ -350,6 +350,7 @@ set(TARGET_LIBM_ENTRYPOINTS
     libc.src.math.nextup
     libc.src.math.nextupf
     libc.src.math.nextupl
+    libc.src.math.pow
     libc.src.math.powf
     libc.src.math.remainder
     libc.src.math.remainderf

libc/config/linux/riscv/entrypoints.txt

@@ -520,6 +520,7 @@ set(TARGET_LIBM_ENTRYPOINTS
     libc.src.math.nextup
     libc.src.math.nextupf
     libc.src.math.nextupl
+    libc.src.math.pow
     libc.src.math.powf
     libc.src.math.remainder
     libc.src.math.remainderf

libc/config/linux/x86_64/entrypoints.txt

@@ -520,6 +520,7 @@ set(TARGET_LIBM_ENTRYPOINTS
     libc.src.math.nextup
     libc.src.math.nextupf
     libc.src.math.nextupl
+    libc.src.math.pow
     libc.src.math.powf
     libc.src.math.remainder
     libc.src.math.remainderf

libc/config/windows/entrypoints.txt

@@ -240,6 +240,7 @@ set(TARGET_LIBM_ENTRYPOINTS
     libc.src.math.nexttoward
     libc.src.math.nexttowardf
     libc.src.math.nexttowardl
+    libc.src.math.pow
     libc.src.math.powf
     libc.src.math.remainderf
     libc.src.math.remainder

libc/docs/math/index.rst

@@ -320,7 +320,7 @@ Higher Math Functions
 +-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
 | logp1     |                  |                 |                        |                      |                        | 7.12.6.14              | F.10.3.14                  |
 +-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
-| pow       | |check|          |                 |                        |                      |                        | 7.12.7.5               | F.10.4.5                   |
+| pow       | |check|          | 1 ULP           |                        |                      |                        | 7.12.7.5               | F.10.4.5                   |
 +-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+
 | powi\*    |                  |                 |                        |                      |                        |                        |                            |
 +-----------+------------------+-----------------+------------------------+----------------------+------------------------+------------------------+----------------------------+

libc/src/math/amdgpu/CMakeLists.txt

@@ -444,18 +444,6 @@ add_entrypoint_object(
   VENDOR
 )
 
-add_entrypoint_object(
-  pow
-  SRCS
-    pow.cpp
-  HDRS
-    ../pow.h
-  COMPILE_OPTIONS
-    ${bitcode_link_flags}
-    -O2
-  VENDOR
-)
-
 add_entrypoint_object(
   powi
   SRCS

libc/src/math/amdgpu/pow.cpp

@@ -1552,6 +1552,29 @@ add_entrypoint_object(
     -O3
 )
 
+add_entrypoint_object(
+  pow
+  SRCS
+    pow.cpp
+  HDRS
+    ../pow.h
+  DEPENDS
+    .common_constants
+    libc.hdr.errno_macros
+    libc.hdr.fenv_macros
+    libc.src.__support.CPP.bit
+    libc.src.__support.FPUtil.double_double
+    libc.src.__support.FPUtil.fenv_impl
+    libc.src.__support.FPUtil.fp_bits
+    libc.src.__support.FPUtil.multiply_add
+    libc.src.__support.FPUtil.nearest_integer
+    libc.src.__support.FPUtil.polyeval
+    libc.src.__support.FPUtil.sqrt
+    libc.src.__support.macros.optimization
+  COMPILE_OPTIONS
+    -O3
+)
+
 add_entrypoint_object(
   copysign
   SRCS