Author: jhb
Date: Wed Dec  4 20:50:49 2019
New Revision: 355402
URL: https://svnweb.freebsd.org/changeset/base/355402

Log:
  Use a single 'ld' to read the jmpbuf magic values instead of 'la; ld'.
  
  This saves an instruction in each case as well as an extra memory
  indirection via the GOT for PIC code.
  
  Reviewed by:  br, James Clarke
  Sponsored by: DARPA
  Differential Revision:        https://reviews.freebsd.org/D22656

Modified:
  head/lib/libc/riscv/gen/_setjmp.S
  head/lib/libc/riscv/gen/setjmp.S

Modified: head/lib/libc/riscv/gen/_setjmp.S
==============================================================================
--- head/lib/libc/riscv/gen/_setjmp.S   Wed Dec  4 20:18:12 2019        
(r355401)
+++ head/lib/libc/riscv/gen/_setjmp.S   Wed Dec  4 20:50:49 2019        
(r355402)
@@ -39,8 +39,7 @@ __FBSDID("$FreeBSD$");
 
 ENTRY(_setjmp)
        /* Store the magic value and stack pointer */
-       la      t0, .Lmagic
-       ld      t0, 0(t0)
+       ld      t0, .Lmagic
        sd      t0, (0 * 8)(a0)
        sd      sp, (1 * 8)(a0)
        addi    a0, a0, (2 * 8)
@@ -89,8 +88,7 @@ END(_setjmp)
 ENTRY(_longjmp)
        /* Check the magic value */
        ld      t0, 0(a0)
-       la      t1, .Lmagic
-       ld      t1, 0(t1)
+       ld      t1, .Lmagic
        bne     t0, t1, botch
 
        /* Restore the stack pointer */

Modified: head/lib/libc/riscv/gen/setjmp.S
==============================================================================
--- head/lib/libc/riscv/gen/setjmp.S    Wed Dec  4 20:18:12 2019        
(r355401)
+++ head/lib/libc/riscv/gen/setjmp.S    Wed Dec  4 20:50:49 2019        
(r355402)
@@ -53,8 +53,7 @@ ENTRY(setjmp)
        addi    sp, sp, (2 * 8)
 
        /* Store the magic value and stack pointer */
-       la      t0, .Lmagic
-       ld      t0, 0(t0)
+       ld      t0, .Lmagic
        sd      t0, (0 * 8)(a0)
        sd      sp, (1 * 8)(a0)
        addi    a0, a0, (2 * 8)
@@ -119,8 +118,7 @@ ENTRY(longjmp)
 
        /* Check the magic value */
        ld      t0, 0(a0)
-       la      t1, .Lmagic
-       ld      t1, 0(t1)
+       ld      t1, .Lmagic
        bne     t0, t1, botch
 
        /* Restore the stack pointer */
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