summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorAlexander Monakov <amonakov@ispras.ru>2020-01-14 23:36:44 +0300
committerRich Felker <dalias@aerifal.cx>2020-03-24 16:31:36 -0400
commitb173e4262f65800ea488b4494125284779a61547 (patch)
tree46cca9389969b9c15bde136bcdd477c80a670c60
parent51f4f8c512d682fe0c1a7a891909e75f416f20f6 (diff)
downloadmusl-b173e4262f65800ea488b4494125284779a61547.tar.gz
math: move x87-family remainder functions to C with inline asm
-rw-r--r--src/math/i386/remainder.c12
-rw-r--r--src/math/i386/remainder.s14
-rw-r--r--src/math/i386/remainderf.c12
-rw-r--r--src/math/i386/remainderf.s14
-rw-r--r--src/math/i386/remainderl.c9
-rw-r--r--src/math/i386/remainderl.s11
-rw-r--r--src/math/x86_64/remainderl.c9
-rw-r--r--src/math/x86_64/remainderl.s11
8 files changed, 42 insertions, 50 deletions
diff --git a/src/math/i386/remainder.c b/src/math/i386/remainder.c
new file mode 100644
index 00000000..c083df90
--- /dev/null
+++ b/src/math/i386/remainder.c
@@ -0,0 +1,12 @@
+#include <math.h>
+
+double remainder(double x, double y)
+{
+ unsigned short fpsr;
+ // fprem1 does not introduce excess precision into x
+ do __asm__ ("fprem1; fnstsw %%ax" : "+t"(x), "=a"(fpsr) : "u"(y));
+ while (fpsr & 0x400);
+ return x;
+}
+
+weak_alias(remainder, drem);
diff --git a/src/math/i386/remainder.s b/src/math/i386/remainder.s
deleted file mode 100644
index ab1da95d..00000000
--- a/src/math/i386/remainder.s
+++ /dev/null
@@ -1,14 +0,0 @@
-.global remainder
-.type remainder,@function
-remainder:
-.weak drem
-.type drem,@function
-drem:
- fldl 12(%esp)
- fldl 4(%esp)
-1: fprem1
- fnstsw %ax
- sahf
- jp 1b
- fstp %st(1)
- ret
diff --git a/src/math/i386/remainderf.c b/src/math/i386/remainderf.c
new file mode 100644
index 00000000..280207d2
--- /dev/null
+++ b/src/math/i386/remainderf.c
@@ -0,0 +1,12 @@
+#include <math.h>
+
+float remainderf(float x, float y)
+{
+ unsigned short fpsr;
+ // fprem1 does not introduce excess precision into x
+ do __asm__ ("fprem1; fnstsw %%ax" : "+t"(x), "=a"(fpsr) : "u"(y));
+ while (fpsr & 0x400);
+ return x;
+}
+
+weak_alias(remainderf, dremf);
diff --git a/src/math/i386/remainderf.s b/src/math/i386/remainderf.s
deleted file mode 100644
index 6a7378a3..00000000
--- a/src/math/i386/remainderf.s
+++ /dev/null
@@ -1,14 +0,0 @@
-.global remainderf
-.type remainderf,@function
-remainderf:
-.weak dremf
-.type dremf,@function
-dremf:
- flds 8(%esp)
- flds 4(%esp)
-1: fprem1
- fnstsw %ax
- sahf
- jp 1b
- fstp %st(1)
- ret
diff --git a/src/math/i386/remainderl.c b/src/math/i386/remainderl.c
new file mode 100644
index 00000000..8cf75071
--- /dev/null
+++ b/src/math/i386/remainderl.c
@@ -0,0 +1,9 @@
+#include <math.h>
+
+long double remainderl(long double x, long double y)
+{
+ unsigned short fpsr;
+ do __asm__ ("fprem1; fnstsw %%ax" : "+t"(x), "=a"(fpsr) : "u"(y));
+ while (fpsr & 0x400);
+ return x;
+}
diff --git a/src/math/i386/remainderl.s b/src/math/i386/remainderl.s
deleted file mode 100644
index b41518ed..00000000
--- a/src/math/i386/remainderl.s
+++ /dev/null
@@ -1,11 +0,0 @@
-.global remainderl
-.type remainderl,@function
-remainderl:
- fldt 16(%esp)
- fldt 4(%esp)
-1: fprem1
- fnstsw %ax
- sahf
- jp 1b
- fstp %st(1)
- ret
diff --git a/src/math/x86_64/remainderl.c b/src/math/x86_64/remainderl.c
new file mode 100644
index 00000000..8cf75071
--- /dev/null
+++ b/src/math/x86_64/remainderl.c
@@ -0,0 +1,9 @@
+#include <math.h>
+
+long double remainderl(long double x, long double y)
+{
+ unsigned short fpsr;
+ do __asm__ ("fprem1; fnstsw %%ax" : "+t"(x), "=a"(fpsr) : "u"(y));
+ while (fpsr & 0x400);
+ return x;
+}
diff --git a/src/math/x86_64/remainderl.s b/src/math/x86_64/remainderl.s
deleted file mode 100644
index cb3857b4..00000000
--- a/src/math/x86_64/remainderl.s
+++ /dev/null
@@ -1,11 +0,0 @@
-.global remainderl
-.type remainderl,@function
-remainderl:
- fldt 24(%rsp)
- fldt 8(%rsp)
-1: fprem1
- fnstsw %ax
- testb $4,%ah
- jnz 1b
- fstp %st(1)
- ret