Do not raise "inexact" from powerpc32 ceil, floor, trunc (bug 15479).

Continuing fixes for ceil, floor and trunc functions not to raise the
"inexact" exception, this patch fixes the versions used on older
powerpc32 processors.  As was done with the round implementations some
time ago, the save of floating-point state is moved after the first
floating-point operation on the input to ensure that any "invalid"
exception from signaling NaN input is included in the saved state, and
then the whole state gets restored rather than just the rounding mode.

This has no effect on configurations using the power5+ code, since
such processors can do these operations with a single instruction (and
those instructions do not set "inexact", so are correct for TS 18661-1
semantics).

Tested for powerpc32.

	[BZ #15479]
	* sysdeps/powerpc/powerpc32/fpu/s_ceil.S (__ceil): Move save of
	floating-point state after first floating-point operation on
	input.  Restore full floating-point state instead of just rounding
	mode.
	* sysdeps/powerpc/powerpc32/fpu/s_ceilf.S (__ceilf): Likewise.
	* sysdeps/powerpc/powerpc32/fpu/s_floor.S (__floor): Likewise.
	* sysdeps/powerpc/powerpc32/fpu/s_floorf.S (__floorf): Likewise.
	* sysdeps/powerpc/powerpc32/fpu/s_trunc.S (__trunc): Likewise.
	* sysdeps/powerpc/powerpc32/fpu/s_truncf.S (__truncf): Likewise.

7 files changed, 49 insertions, 18 deletions

diff --git a/ChangeLog b/ChangeLog
index 1ecd6d5ab9..4564571809 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,16 @@
+2016-05-25  Joseph Myers  <joseph@codesourcery.com>
+
+	[BZ #15479]
+	* sysdeps/powerpc/powerpc32/fpu/s_ceil.S (__ceil): Move save of
+	floating-point state after first floating-point operation on
+	input.  Restore full floating-point state instead of just rounding
+	mode.
+	* sysdeps/powerpc/powerpc32/fpu/s_ceilf.S (__ceilf): Likewise.
+	* sysdeps/powerpc/powerpc32/fpu/s_floor.S (__floor): Likewise.
+	* sysdeps/powerpc/powerpc32/fpu/s_floorf.S (__floorf): Likewise.
+	* sysdeps/powerpc/powerpc32/fpu/s_trunc.S (__trunc): Likewise.
+	* sysdeps/powerpc/powerpc32/fpu/s_truncf.S (__truncf): Likewise.
+
 2016-05-25  Stefan Liebler  <stli@linux.vnet.ibm.com>
 
 	[BZ #19727]
diff --git a/sysdeps/powerpc/powerpc32/fpu/s_ceil.S b/sysdeps/powerpc/powerpc32/fpu/s_ceil.S
index 48d6d0de19..07d031e22e 100644
--- a/sysdeps/powerpc/powerpc32/fpu/s_ceil.S
+++ b/sysdeps/powerpc/powerpc32/fpu/s_ceil.S
@@ -26,7 +26,6 @@
 
 	.section	".text"
 ENTRY (__ceil)
-	mffs	fp11		/* Save current FPU rounding mode.  */
 #ifdef SHARED
 	mflr	r11
 	cfi_register(lr,r11)
@@ -42,6 +41,8 @@ ENTRY (__ceil)
 	fabs	fp0,fp1
 	fsub	fp12,fp13,fp13	/* generate 0.0  */
 	fcmpu	cr7,fp0,fp13	/* if (fabs(x) > TWO52)  */
+	mffs	fp11		/* Save current FPU rounding mode and
+				   "inexact" state.  */
 	fcmpu	cr6,fp1,fp12	/* if (x > 0.0)  */
 	bnllr-	cr7
 	mtfsfi	7,2		/* Set rounding mode toward +inf.  */
@@ -50,7 +51,8 @@ ENTRY (__ceil)
 	fsub	fp1,fp1,fp13	/* x-= TWO52;  */
 	fabs	fp1,fp1		/* if (x == 0.0)  */
 				/* x = 0.0; */
-	mtfsf	0x01,fp11	/* restore previous rounding mode.  */
+	mtfsf	0xff,fp11	/* Restore previous rounding mode and
+				   "inexact" state.  */
 	blr
 .L4:
 	bge-	cr6,.L9		/* if (x < 0.0)  */
@@ -59,7 +61,8 @@ ENTRY (__ceil)
 	fnabs	fp1,fp1		/* if (x == 0.0)  */
 				/* x = -0.0; */
 .L9:
-	mtfsf	0x01,fp11	/* restore previous rounding mode.  */
+	mtfsf	0xff,fp11	/* Restore previous rounding mode and
+				   "inexact" state.  */
 	blr
 	END (__ceil)
 
diff --git a/sysdeps/powerpc/powerpc32/fpu/s_ceilf.S b/sysdeps/powerpc/powerpc32/fpu/s_ceilf.S
index c70fd444e2..3987e24e41 100644
--- a/sysdeps/powerpc/powerpc32/fpu/s_ceilf.S
+++ b/sysdeps/powerpc/powerpc32/fpu/s_ceilf.S
@@ -25,7 +25,6 @@
 
 	.section	".text"
 ENTRY (__ceilf)
-	mffs	fp11		/* Save current FPU rounding mode.  */
 #ifdef SHARED
 	mflr	r11
 	cfi_register(lr,r11)
@@ -41,6 +40,8 @@ ENTRY (__ceilf)
 	fabs	fp0,fp1
 	fsubs	fp12,fp13,fp13	/* generate 0.0  */
 	fcmpu	cr7,fp0,fp13	/* if (fabs(x) > TWO23)  */
+	mffs	fp11		/* Save current FPU rounding mode and
+				   "inexact" state.  */
 	fcmpu	cr6,fp1,fp12	/* if (x > 0.0)  */
 	bnllr-	cr7
 	mtfsfi	7,2		/* Set rounding mode toward +inf.  */
@@ -49,7 +50,8 @@ ENTRY (__ceilf)
 	fsubs	fp1,fp1,fp13	/* x-= TWO23;  */
 	fabs	fp1,fp1		/* if (x == 0.0)  */
 				/* x = 0.0; */
-	mtfsf	0x01,fp11	/* restore previous rounding mode.  */
+	mtfsf	0xff,fp11	/* Restore previous rounding mode and
+				   "inexact" state.  */
 	blr
 .L4:
 	bge-	cr6,.L9		/* if (x < 0.0)  */
@@ -58,7 +60,8 @@ ENTRY (__ceilf)
 	fnabs	fp1,fp1		/* if (x == 0.0)  */
 				/* x = -0.0; */
 .L9:
-	mtfsf	0x01,fp11	/* restore previous rounding mode.  */
+	mtfsf	0xff,fp11	/* Restore previous rounding mode and
+				   "inexact" state.  */
 	blr
 	END (__ceilf)
 
diff --git a/sysdeps/powerpc/powerpc32/fpu/s_floor.S b/sysdeps/powerpc/powerpc32/fpu/s_floor.S
index 3f84465a8e..b951666bd7 100644
--- a/sysdeps/powerpc/powerpc32/fpu/s_floor.S
+++ b/sysdeps/powerpc/powerpc32/fpu/s_floor.S
@@ -26,7 +26,6 @@
 
 	.section	".text"
 ENTRY (__floor)
-	mffs	fp11		/* Save current FPU rounding mode.  */
 #ifdef SHARED
 	mflr	r11
 	cfi_register(lr,r11)
@@ -42,6 +41,8 @@ ENTRY (__floor)
 	fabs	fp0,fp1
 	fsub	fp12,fp13,fp13	/* generate 0.0  */
 	fcmpu	cr7,fp0,fp13	/* if (fabs(x) > TWO52)  */
+	mffs	fp11		/* Save current FPU rounding mode and
+				   "inexact" state.  */
 	fcmpu	cr6,fp1,fp12	/* if (x > 0.0)  */
 	bnllr-	cr7
 	mtfsfi	7,3		/* Set rounding mode toward -inf.  */
@@ -50,7 +51,8 @@ ENTRY (__floor)
 	fsub	fp1,fp1,fp13	/* x-= TWO52;  */
 	fabs	fp1,fp1		/* if (x == 0.0)  */
 				/* x = 0.0; */
-	mtfsf	0x01,fp11	/* restore previous rounding mode.  */
+	mtfsf	0xff,fp11	/* Restore previous rounding mode and
+				   "inexact" state.  */
 	blr
 .L4:
 	bge-	cr6,.L9		/* if (x < 0.0)  */
@@ -59,7 +61,8 @@ ENTRY (__floor)
 	fnabs	fp1,fp1		/* if (x == 0.0)  */
 				/* x = -0.0; */
 .L9:
-	mtfsf	0x01,fp11	/* restore previous rounding mode.  */
+	mtfsf	0xff,fp11	/* Restore previous rounding mode and
+				   "inexact" state.  */
 	blr
 	END (__floor)
 
diff --git a/sysdeps/powerpc/powerpc32/fpu/s_floorf.S b/sysdeps/powerpc/powerpc32/fpu/s_floorf.S
index 55ac526d71..64b87b1cc1 100644
--- a/sysdeps/powerpc/powerpc32/fpu/s_floorf.S
+++ b/sysdeps/powerpc/powerpc32/fpu/s_floorf.S
@@ -25,7 +25,6 @@
 
 	.section	".text"
 ENTRY (__floorf)
-	mffs	fp11		/* Save current FPU rounding mode.  */
 #ifdef SHARED
 	mflr	r11
 	cfi_register(lr,r11)
@@ -41,6 +40,8 @@ ENTRY (__floorf)
 	fabs	fp0,fp1
 	fsubs	fp12,fp13,fp13	/* generate 0.0  */
 	fcmpu	cr7,fp0,fp13	/* if (fabs(x) > TWO23)  */
+	mffs	fp11		/* Save current FPU rounding mode and
+				   "inexact" state.  */
 	fcmpu	cr6,fp1,fp12	/* if (x > 0.0)  */
 	bnllr-	cr7
 	mtfsfi	7,3		/* Set rounding mode toward -inf.  */
@@ -49,7 +50,8 @@ ENTRY (__floorf)
 	fsubs	fp1,fp1,fp13	/* x-= TWO23;  */
 	fabs	fp1,fp1		/* if (x == 0.0)  */
 				/* x = 0.0; */
-	mtfsf	0x01,fp11	/* restore previous rounding mode.  */
+	mtfsf	0xff,fp11	/* Restore previous rounding mode and
+				   "inexact" state.  */
 	blr
 .L4:
 	bge-	cr6,.L9		/* if (x < 0.0)  */
@@ -58,7 +60,8 @@ ENTRY (__floorf)
 	fnabs	fp1,fp1		/* if (x == 0.0)  */
 				/* x = -0.0; */
 .L9:
-	mtfsf	0x01,fp11	/* restore previous rounding mode.  */
+	mtfsf	0xff,fp11	/* Restore previous rounding mode and
+				   "inexact" state.  */
 	blr
 	END (__floorf)
 
diff --git a/sysdeps/powerpc/powerpc32/fpu/s_trunc.S b/sysdeps/powerpc/powerpc32/fpu/s_trunc.S
index c8aa2fb245..260b4fd336 100644
--- a/sysdeps/powerpc/powerpc32/fpu/s_trunc.S
+++ b/sysdeps/powerpc/powerpc32/fpu/s_trunc.S
@@ -33,7 +33,6 @@
 
 	.section	".text"
 ENTRY (__trunc)
-	mffs	fp11		/* Save current FPU rounding mode.  */
 #ifdef SHARED
 	mflr	r11
 	cfi_register(lr,r11)
@@ -49,6 +48,8 @@ ENTRY (__trunc)
 	fabs	fp0,fp1
 	fsub	fp12,fp13,fp13	/* generate 0.0  */
 	fcmpu	cr7,fp0,fp13	/* if (fabs(x) > TWO52)  */
+	mffs	fp11		/* Save current FPU rounding mode and
+				   "inexact" state.  */
 	fcmpu	cr6,fp1,fp12	/* if (x > 0.0)  */
 	bnllr-	cr7
 	mtfsfi	7,1		/* Set rounding toward 0 mode.  */
@@ -57,7 +58,8 @@ ENTRY (__trunc)
 	fsub	fp1,fp1,fp13	/* x-= TWO52;  */
 	fabs	fp1,fp1		/* if (x == 0.0)  */
 				/* x = 0.0; */
-	mtfsf	0x01,fp11	/* restore previous rounding mode.  */
+	mtfsf	0xff,fp11	/* Restore previous rounding mode and
+				   "inexact" state.  */
 	blr
 .L4:
 	bge-	cr6,.L9		/* if (x < 0.0)  */
@@ -66,7 +68,8 @@ ENTRY (__trunc)
 	fnabs	fp1,fp1		/* if (x == 0.0)  */
 				/* x = -0.0; */
 .L9:
-	mtfsf	0x01,fp11	/* restore previous rounding mode.  */
+	mtfsf	0xff,fp11	/* Restore previous rounding mode and
+				   "inexact" state.  */
 	blr
 	END (__trunc)
 
diff --git a/sysdeps/powerpc/powerpc32/fpu/s_truncf.S b/sysdeps/powerpc/powerpc32/fpu/s_truncf.S
index e47ee96c55..6c2c959e71 100644
--- a/sysdeps/powerpc/powerpc32/fpu/s_truncf.S
+++ b/sysdeps/powerpc/powerpc32/fpu/s_truncf.S
@@ -32,7 +32,6 @@
 
 	.section	".text"
 ENTRY (__truncf)
-	mffs	fp11		/* Save current FPU rounding mode.  */
 #ifdef SHARED
 	mflr	r11
 	cfi_register(lr,r11)
@@ -48,6 +47,8 @@ ENTRY (__truncf)
 	fabs	fp0,fp1
 	fsubs	fp12,fp13,fp13	/* generate 0.0  */
 	fcmpu	cr7,fp0,fp13	/* if (fabs(x) > TWO23)  */
+	mffs	fp11		/* Save current FPU rounding mode and
+				   "inexact" state.  */
 	fcmpu	cr6,fp1,fp12	/* if (x > 0.0)  */
 	bnllr-	cr7
 	mtfsfi	7,1		/* Set rounding toward 0 mode.  */
@@ -56,7 +57,8 @@ ENTRY (__truncf)
 	fsubs	fp1,fp1,fp13	/* x-= TWO23;  */
 	fabs	fp1,fp1		/* if (x == 0.0)  */
 				/* x = 0.0; */
-	mtfsf	0x01,fp11	/* restore previous rounding mode.  */
+	mtfsf	0xff,fp11	/* Restore previous rounding mode and
+				   "inexact" state.  */
 	blr
 .L4:
 	bge-	cr6,.L9		/* if (x < 0.0)  */
@@ -65,7 +67,8 @@ ENTRY (__truncf)
 	fnabs	fp1,fp1		/* if (x == 0.0)  */
 				/* x = -0.0; */
 .L9:
-	mtfsf	0x01,fp11	/* restore previous rounding mode.  */
+	mtfsf	0xff,fp11	/* Restore previous rounding mode and
+				   "inexact" state.  */
 	blr
 	END (__truncf)