svn commit: r295148 - in stable/10/sys: amd64/amd64 i386/isa

[Konstantin Belousov]

Author: kib
Date: Tue Feb  2 14:16:07 2016
New Revision: 295148
URL: https://svnweb.freebsd.org/changeset/base/295148

Log:
  MFC r294311:
  Clear whole XMM register file instead of only XMM0.  Also clear x87
  registers.  This brings amd64 on par with i386, providing consistent
  initial FPU state.
  
  PR:	206370
  
  MFC r294312:
  Use ANSI definitions.  Wrap long line.
  
  MFC r294313:
  Adjust i386 comment to match amd64 one after r294311.
  
  Approved by:	re (gjb)

Modified:
  stable/10/sys/amd64/amd64/fpu.c
  stable/10/sys/i386/isa/npx.c
Directory Properties:
  stable/10/   (props changed)

Modified: stable/10/sys/amd64/amd64/fpu.c
==============================================================================
--- stable/10/sys/amd64/amd64/fpu.c	Tue Feb  2 11:51:18 2016	(r295147)
+++ stable/10/sys/amd64/amd64/fpu.c	Tue Feb  2 14:16:07 2016	(r295148)
@@ -318,13 +318,15 @@ fpuinitstate(void *arg __unused)
 		cpu_mxcsr_mask = 0xFFBF;
 
 	/*
-	 * The fninit instruction does not modify XMM registers.  The
-	 * fpusave call dumped the garbage contained in the registers
-	 * after reset to the initial state saved.  Clear XMM
-	 * registers file image to make the startup program state and
-	 * signal handler XMM register content predictable.
+	 * The fninit instruction does not modify XMM registers or x87
+	 * registers (MM/ST).  The fpusave call dumped the garbage
+	 * contained in the registers after reset to the initial state
+	 * saved.  Clear XMM and x87 registers file image to make the
+	 * startup program state and signal handler XMM/x87 register
+	 * content predictable.
 	 */
-	bzero(&fpu_initialstate->sv_xmm[0], sizeof(struct xmmacc));
+	bzero(fpu_initialstate->sv_fp, sizeof(fpu_initialstate->sv_fp));
+	bzero(fpu_initialstate->sv_xmm, sizeof(fpu_initialstate->sv_xmm));
 
 	/*
 	 * Create a table describing the layout of the CPU Extended
@@ -375,7 +377,7 @@ fpuexit(struct thread *td)
 }
 
 int
-fpuformat()
+fpuformat(void)
 {
 
 	return (_MC_FPFMT_XMM);
@@ -661,7 +663,8 @@ fpudna(void)
 		 * fpu_initialstate, to ignite the XSAVEOPT
 		 * tracking engine.
 		 */
-		bcopy(fpu_initialstate, curpcb->pcb_save, cpu_max_ext_state_size);
+		bcopy(fpu_initialstate, curpcb->pcb_save,
+		    cpu_max_ext_state_size);
 		fpurestore(curpcb->pcb_save);
 		if (curpcb->pcb_initial_fpucw != __INITIAL_FPUCW__)
 			fldcw(curpcb->pcb_initial_fpucw);
@@ -676,7 +679,7 @@ fpudna(void)
 }
 
 void
-fpudrop()
+fpudrop(void)
 {
 	struct thread *td;
 

Modified: stable/10/sys/i386/isa/npx.c
==============================================================================
--- stable/10/sys/i386/isa/npx.c	Tue Feb  2 11:51:18 2016	(r295147)
+++ stable/10/sys/i386/isa/npx.c	Tue Feb  2 14:16:07 2016	(r295148)
@@ -503,11 +503,12 @@ npxinitstate(void *arg __unused)
 
 		/*
 		 * The fninit instruction does not modify XMM
-		 * registers.  The fpusave call dumped the garbage
-		 * contained in the registers after reset to the
-		 * initial state saved.  Clear XMM registers file
-		 * image to make the startup program state and signal
-		 * handler XMM register content predictable.
+		 * registers or x87 registers (MM/ST).  The fpusave
+		 * call dumped the garbage contained in the registers
+		 * after reset to the initial state saved.  Clear XMM
+		 * and x87 registers file image to make the startup
+		 * program state and signal handler XMM/x87 register
+		 * content predictable.
 		 */
 		bzero(npx_initialstate->sv_xmm.sv_fp,
 		    sizeof(npx_initialstate->sv_xmm.sv_fp));