s390x: Use loop to save and restore fprs

PATCH In review Janosch Frank 4 participants 4 messages Nov 4, 2019 – Nov 11, 2019

Subsystems (2)

KVM s390

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Janosch Frank

author

2019-11-04 08:56 UTC #0 lore raw

PATCH 1/1 s390x: Use loop to save and restore fprs

Let's save some lines in the assembly by using a loop to save and restore the fprs.

Signed-off-by Janosch Frank <[email protected]>

---
 s390x/cstart64.S | 38 ++++++--------------------------------
 1 file changed, 6 insertions(+), 32 deletions(-)

s390x/cstart64.S +6 ~~-32~~

index 5dc1577..8e2b21e 100644
@@ -99,44 +99,18 @@ memsetxc:
 	lctlg	%c0, %c0, 0(%r1)
 	/* save fprs 0-15 + fpc */
 	la	%r1, GEN_LC_SW_INT_FPRS
-	std	%f0, 0(%r1)
-	std	%f1, 8(%r1)
-	std	%f2, 16(%r1)
-	std	%f3, 24(%r1)
-	std	%f4, 32(%r1)
-	std	%f5, 40(%r1)
-	std	%f6, 48(%r1)
-	std	%f7, 56(%r1)
-	std	%f8, 64(%r1)
-	std	%f9, 72(%r1)
-	std	%f10, 80(%r1)
-	std	%f11, 88(%r1)
-	std	%f12, 96(%r1)
-	std	%f13, 104(%r1)
-	std	%f14, 112(%r1)
-	std	%f15, 120(%r1)
+	.irp i, 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15
+	std	\i, \i * 8(%r1)
+	.endr
 	stfpc	GEN_LC_SW_INT_FPC
 	.endm
 
 	.macro RESTORE_REGS
 	/* restore fprs 0-15 + fpc */
 	la	%r1, GEN_LC_SW_INT_FPRS
-	ld	%f0, 0(%r1)
-	ld	%f1, 8(%r1)
-	ld	%f2, 16(%r1)
-	ld	%f3, 24(%r1)
-	ld	%f4, 32(%r1)
-	ld	%f5, 40(%r1)
-	ld	%f6, 48(%r1)
-	ld	%f7, 56(%r1)
-	ld	%f8, 64(%r1)
-	ld	%f9, 72(%r1)
-	ld	%f10, 80(%r1)
-	ld	%f11, 88(%r1)
-	ld	%f12, 96(%r1)
-	ld	%f13, 104(%r1)
-	ld	%f14, 112(%r1)
-	ld	%f15, 120(%r1)
+	.irp i, 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15
+	ld	\i, \i * 8(%r1)
+	.endr
 	lfpc	GEN_LC_SW_INT_FPC
 	/* restore cr0 */
 	lctlg	%c0, %c0, GEN_LC_SW_INT_CR0

Signature · 1 line

2.20.1

David Hildenbrand

2019-11-04 10:00 UTC #1 lore raw

Quoted 54 lines · Janosch Frank

Let's save some lines in the assembly by using a loop to save and restore the fprs.

Signed-off-by Janosch Frank <[email protected]>

---
  s390x/cstart64.S | 38 ++++++--------------------------------
  1 file changed, 6 insertions(+), 32 deletions(-)

s390x/cstart64.S +3 ~~-28~~

index 5dc1577..8e2b21e 100644
@@ -99,44 +99,18 @@ memsetxc:
  	lctlg	%c0, %c0, 0(%r1)
  	/* save fprs 0-15 + fpc */
  	la	%r1, GEN_LC_SW_INT_FPRS
-	std	%f0, 0(%r1)
-	std	%f1, 8(%r1)
-	std	%f2, 16(%r1)
-	std	%f3, 24(%r1)
-	std	%f4, 32(%r1)
-	std	%f5, 40(%r1)
-	std	%f6, 48(%r1)
-	std	%f7, 56(%r1)
-	std	%f8, 64(%r1)
-	std	%f9, 72(%r1)
-	std	%f10, 80(%r1)
-	std	%f11, 88(%r1)
-	std	%f12, 96(%r1)
-	std	%f13, 104(%r1)
-	std	%f14, 112(%r1)
-	std	%f15, 120(%r1)
+	.irp i, 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15
+	std	\i, \i * 8(%r1)
+	.endr
  	stfpc	GEN_LC_SW_INT_FPC
  	.endm
 
  	.macro RESTORE_REGS
  	/* restore fprs 0-15 + fpc */
  	la	%r1, GEN_LC_SW_INT_FPRS
-	ld	%f0, 0(%r1)
-	ld	%f1, 8(%r1)
-	ld	%f2, 16(%r1)
-	ld	%f3, 24(%r1)
-	ld	%f4, 32(%r1)
-	ld	%f5, 40(%r1)
-	ld	%f6, 48(%r1)
-	ld	%f7, 56(%r1)
-	ld	%f8, 64(%r1)
-	ld	%f9, 72(%r1)
-	ld	%f10, 80(%r1)
-	ld	%f11, 88(%r1)

s390x/cstart64.S memsetxc: · line 116

Quoted 10 lines

s390x/cstart64.S +3 -4

-	ld	%f12, 96(%r1)
-	ld	%f13, 104(%r1)
-	ld	%f14, 112(%r1)
-	ld	%f15, 120(%r1)
+	.irp i, 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15
+	ld	\i, \i * 8(%r1)
+	.endr
  	lfpc	GEN_LC_SW_INT_FPC
  	/* restore cr0 */
  	lctlg	%c0, %c0, GEN_LC_SW_INT_CR0

Looks good to me!

Queued to

https://github.com/davidhildenbrand/kvm-unit-tests.git s390x-next

For now, but waiting for more review.

Signature · 3 lines

Thanks,

David / dhildenb

Thomas Huth

Tested-by on v1 1/1

2019-11-08 09:15 UTC #2 lore raw

In reply to Janosch Frank

Quoted 54 lines · Janosch Frank

Let's save some lines in the assembly by using a loop to save and restore the fprs.

Signed-off-by Janosch Frank <[email protected]>

---
  s390x/cstart64.S | 38 ++++++--------------------------------
  1 file changed, 6 insertions(+), 32 deletions(-)

s390x/cstart64.S +3 ~~-28~~

index 5dc1577..8e2b21e 100644
@@ -99,44 +99,18 @@ memsetxc:
  	lctlg	%c0, %c0, 0(%r1)
  	/* save fprs 0-15 + fpc */
  	la	%r1, GEN_LC_SW_INT_FPRS
-	std	%f0, 0(%r1)
-	std	%f1, 8(%r1)
-	std	%f2, 16(%r1)
-	std	%f3, 24(%r1)
-	std	%f4, 32(%r1)
-	std	%f5, 40(%r1)
-	std	%f6, 48(%r1)
-	std	%f7, 56(%r1)
-	std	%f8, 64(%r1)
-	std	%f9, 72(%r1)
-	std	%f10, 80(%r1)
-	std	%f11, 88(%r1)
-	std	%f12, 96(%r1)
-	std	%f13, 104(%r1)
-	std	%f14, 112(%r1)
-	std	%f15, 120(%r1)
+	.irp i, 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15
+	std	\i, \i * 8(%r1)
+	.endr
  	stfpc	GEN_LC_SW_INT_FPC
  	.endm
 
  	.macro RESTORE_REGS
  	/* restore fprs 0-15 + fpc */
  	la	%r1, GEN_LC_SW_INT_FPRS
-	ld	%f0, 0(%r1)
-	ld	%f1, 8(%r1)
-	ld	%f2, 16(%r1)
-	ld	%f3, 24(%r1)
-	ld	%f4, 32(%r1)
-	ld	%f5, 40(%r1)
-	ld	%f6, 48(%r1)
-	ld	%f7, 56(%r1)
-	ld	%f8, 64(%r1)
-	ld	%f9, 72(%r1)
-	ld	%f10, 80(%r1)
-	ld	%f11, 88(%r1)

s390x/cstart64.S memsetxc: · line 116

Quoted 10 lines

s390x/cstart64.S +3 -4

-	ld	%f12, 96(%r1)
-	ld	%f13, 104(%r1)
-	ld	%f14, 112(%r1)
-	ld	%f15, 120(%r1)
+	.irp i, 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15
+	ld	\i, \i * 8(%r1)
+	.endr
  	lfpc	GEN_LC_SW_INT_FPC
  	/* restore cr0 */
  	lctlg	%c0, %c0, GEN_LC_SW_INT_CR0

Produces exactly the same code as before.

Tested-by Thomas Huth <[email protected]>

Pierre Morel

Reviewed-by

2019-11-11 13:34 UTC #3 lore raw

Quoted 67 lines · Thomas Huth

Quoted 54 lines · Janosch Frank
Let's save some lines in the assembly by using a loop to save and restore the fprs.
Signed-off-by Janosch Frank <[email protected]>
---
s390x/cstart64.S | 38 ++++++--------------------------------
  1 file changed, 6 insertions(+), 32 deletions(-)
s390x/cstart64.S +0 -0
index 5dc1577..8e2b21e 100644
@@ -99,44 +99,18 @@ memsetxc:
       lctlg    %c0, %c0, 0(%r1)
       /* save fprs 0-15 + fpc */
      la    %r1, GEN_LC_SW_INT_FPRS
-    std    %f0, 0(%r1)
-    std    %f1, 8(%r1)
-    std    %f2, 16(%r1)
-    std    %f3, 24(%r1)
-    std    %f4, 32(%r1)
-    std    %f5, 40(%r1)
-    std    %f6, 48(%r1)
-    std    %f7, 56(%r1)
-    std    %f8, 64(%r1)
-    std    %f9, 72(%r1)
-    std    %f10, 80(%r1)
-    std    %f11, 88(%r1)
-    std    %f12, 96(%r1)
-    std    %f13, 104(%r1)
-    std    %f14, 112(%r1)
-    std    %f15, 120(%r1)
+    .irp i, 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15 +    std    \i, \i * 8(%r1)
+    .endr
      stfpc    GEN_LC_SW_INT_FPC
      .endm
      .macro RESTORE_REGS
      /* restore fprs 0-15 + fpc */
      la    %r1, GEN_LC_SW_INT_FPRS
-    ld    %f0, 0(%r1)
-    ld    %f1, 8(%r1)
-    ld    %f2, 16(%r1)
-    ld    %f3, 24(%r1)
-    ld    %f4, 32(%r1)
-    ld    %f5, 40(%r1)
-    ld    %f6, 48(%r1)
-    ld    %f7, 56(%r1)
-    ld    %f8, 64(%r1)
-    ld    %f9, 72(%r1)
-    ld    %f10, 80(%r1)
-    ld    %f11, 88(%r1)
-    ld    %f12, 96(%r1)
-    ld    %f13, 104(%r1)
Quoted 9 lines
-    ld    %f14, 112(%r1)
-    ld    %f15, 120(%r1)
+    .irp i, 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15 +    ld    \i, \i * 8(%r1)
+    .endr
      lfpc    GEN_LC_SW_INT_FPC
      /* restore cr0 */
      lctlg    %c0, %c0, GEN_LC_SW_INT_CR0
Produces exactly the same code as before.

Quoted 2 lines

Tested-by Thomas Huth <[email protected]>

Good for me, makes the code smaller ... is better

Reviewed-by Pierre Morel <[email protected]>

Signature · 2 lines

Pierre Morel
IBM Lab Boeblingen