[Valgrind-developers] [valgrind] s390: PFPO facility related cleanups (BZ 509562)

[Florian K. <fk...@so...>]

https://sourceware.org/cgit/valgrind/commit/?id=5e0aa0cefa62fe3a9f712befb21e50650b9b3dea

commit 5e0aa0cefa62fe3a9f712befb21e50650b9b3dea
Author: Florian Krohm <fl...@ei...>
Date:   Tue Nov 25 13:50:37 2025 +0000

    s390: PFPO facility related cleanups  (BZ 509562)
    
    The PFPO facility is always present on the supported machines.
    - Remove VEX_HWCAPS_S390X_PFPO, s390_host_has_pfpo and EmFail_S390X_pfpo
    - Update tests/s390x_features.c and none/tests/s390x/pfpo
    - Update memcheck/tests/vbit-test
    
    Part of fixing https://bugs.kde.org/show_bug.cgi?id=509562

Diff:
---
 VEX/priv/guest_s390_toIR.c       |  5 -----
 VEX/priv/host_s390_defs.c        |  1 -
 VEX/priv/host_s390_defs.h        |  2 --
 VEX/priv/main_main.c             |  3 ---
 VEX/pub/libvex.h                 |  4 +---
 VEX/pub/libvex_emnote.h          |  3 ---
 coregrind/m_machine.c            |  1 -
 memcheck/tests/vbit-test/irops.c | 10 +---------
 none/tests/s390x/pfpo.vgtest     |  1 -
 tests/s390x_features.c           |  2 --
 10 files changed, 2 insertions(+), 30 deletions(-)

diff --git a/VEX/priv/guest_s390_toIR.c b/VEX/priv/guest_s390_toIR.c
index b01849cb67..8f42c844d3 100644
--- a/VEX/priv/guest_s390_toIR.c
+++ b/VEX/priv/guest_s390_toIR.c
@@ -9530,11 +9530,6 @@ s390_call_pfpo_helper(IRExpr *gr0)
 static const HChar *
 s390_irgen_PFPO(void)
 {
-   if (! s390_host_has_pfpo) {
-      emulation_failure(EmFail_S390X_pfpo);
-      return "pfpo";
-   }
-
    IRTemp gr0 = newTemp(Ity_I32);     /* word 1 [32:63] of GR 0 */
    IRTemp test_bit = newTemp(Ity_I32); /* bit 32 of GR 0 - test validity */
    IRTemp fn = newTemp(Ity_I32);       /* [33:55] of GR 0 - function code */
diff --git a/VEX/priv/host_s390_defs.c b/VEX/priv/host_s390_defs.c
index 9482193425..96c566823b 100644
--- a/VEX/priv/host_s390_defs.c
+++ b/VEX/priv/host_s390_defs.c
@@ -4838,7 +4838,6 @@ emit_E(UChar *p, UInt op)
 static UChar *
 s390_emit_PFPO(UChar *p)
 {
-   vassert(s390_host_has_pfpo);
    if (UNLIKELY(vex_traceflags & VEX_TRACE_ASM)) {
       S390_DISASM(MNM("pfpo"));
    }
diff --git a/VEX/priv/host_s390_defs.h b/VEX/priv/host_s390_defs.h
index b660b70776..f089eac9a1 100644
--- a/VEX/priv/host_s390_defs.h
+++ b/VEX/priv/host_s390_defs.h
@@ -918,8 +918,6 @@ VexInvalRange patchProfInc_S390(VexEndness endness_host,
 extern UInt s390_host_hwcaps;
 
 /* Convenience macros to test installed facilities */
-#define s390_host_has_pfpo \
-                      (s390_host_hwcaps & (VEX_HWCAPS_S390X_PFPO))
 #define s390_host_has_vx \
                       (s390_host_hwcaps & (VEX_HWCAPS_S390X_VX))
 #define s390_host_has_msa5 \
diff --git a/VEX/priv/main_main.c b/VEX/priv/main_main.c
index 9783d0e313..32a78190ad 100644
--- a/VEX/priv/main_main.c
+++ b/VEX/priv/main_main.c
@@ -1544,8 +1544,6 @@ const HChar* LibVEX_EmNote_string ( VexEmNote ew )
         return "Encountered an insn with the IEEE-invalid-operation-exception\n"
                "  control (XiC) bit set to 1. This is not supported. Continuing anyway.\n"
                "  IEEE-invalid-operation exceptions will not be suppressed.";
-     case EmFail_S390X_pfpo:
-        return "Instruction pfpo is not supported on this host";
      case EmFail_S390X_invalid_PFPO_rounding_mode:
         return "The rounding mode in GPR 0 for the PFPO instruction"
                " is invalid";
@@ -1902,7 +1900,6 @@ static const HChar* show_hwcaps_s390x ( UInt hwcaps )
       UInt  hwcaps_bit;
       HChar name[6];
    } hwcaps_list[] = {
-      { VEX_HWCAPS_S390X_PFPO,  "pfpo" },
       { VEX_HWCAPS_S390X_VX,    "vx" },
       { VEX_HWCAPS_S390X_MSA5,  "msa5" },
       { VEX_HWCAPS_S390X_MI2,   "mi2" },
diff --git a/VEX/pub/libvex.h b/VEX/pub/libvex.h
index 3fcecd00fd..07c39eb4ea 100644
--- a/VEX/pub/libvex.h
+++ b/VEX/pub/libvex.h
@@ -162,7 +162,6 @@ typedef
 #define VEX_S390X_MODEL_UNKNOWN  19     /* always last in list */
 #define VEX_S390X_MODEL_MASK     0x3F
 
-#define VEX_HWCAPS_S390X_PFPO  (1<<17)  /* Perform floating point ops facility */
 #define VEX_HWCAPS_S390X_VX    (1<<18)  /* Vector facility */
 #define VEX_HWCAPS_S390X_MSA5  (1<<19)  /* Message-security-assistance facility 5 */
 #define VEX_HWCAPS_S390X_MI2   (1<<20)  /* Miscellaneous-instruction-extensions facility 2 */
@@ -176,8 +175,7 @@ typedef
 #define VEX_HWCAPS_S390X_MSA9  (1<<30)  /* Message-security-assist extension 9 */
 
 /* Special value representing all available s390x hwcaps */
-#define VEX_HWCAPS_S390X_ALL   (VEX_HWCAPS_S390X_PFPO  | \
-                                VEX_HWCAPS_S390X_VX    | \
+#define VEX_HWCAPS_S390X_ALL   (VEX_HWCAPS_S390X_VX    | \
                                 VEX_HWCAPS_S390X_MSA5  | \
                                 VEX_HWCAPS_S390X_MI2   | \
                                 VEX_HWCAPS_S390X_LSC2  | \
diff --git a/VEX/pub/libvex_emnote.h b/VEX/pub/libvex_emnote.h
index 04a9e0a6e6..a3fa196520 100644
--- a/VEX/pub/libvex_emnote.h
+++ b/VEX/pub/libvex_emnote.h
@@ -94,9 +94,6 @@ typedef
          in VEX and is expected to be zero. */
       EmWarn_S390X_XiC_not_zero,
 
-      /* pfpo insn is not supported on this host */
-      EmFail_S390X_pfpo,
-
       /* GPR 0 contains invalid rounding mode for PFPO instruction */
       EmFail_S390X_invalid_PFPO_rounding_mode,
 
diff --git a/coregrind/m_machine.c b/coregrind/m_machine.c
index e285ec3d39..01a50c9b2c 100644
--- a/coregrind/m_machine.c
+++ b/coregrind/m_machine.c
@@ -1565,7 +1565,6 @@ Bool VG_(machine_get_hwcaps)( void )
         UInt hwcaps_bit;
         const HChar name[6];   // may need adjustment for new facility names
      } fac_hwcaps[] = {
-        { False,  44,  VEX_HWCAPS_S390X_PFPO,  "PFPO"  },
         { False, 129,  VEX_HWCAPS_S390X_VX,    "VX"    },
         { False,  57,  VEX_HWCAPS_S390X_MSA5,  "MSA5"  },
         { False,  58,  VEX_HWCAPS_S390X_MI2,   "MI2"   },
diff --git a/memcheck/tests/vbit-test/irops.c b/memcheck/tests/vbit-test/irops.c
index e3e06d7c78..8cd400e62a 100644
--- a/memcheck/tests/vbit-test/irops.c
+++ b/memcheck/tests/vbit-test/irops.c
@@ -1208,7 +1208,6 @@ get_irop(IROp op)
       if (p->op == op) {
 #ifdef __s390x__
 #define S390X_FEATURES "../../../tests/s390x_features"
-        int rc;
 
          switch (op) {
          case Iop_I32StoD64:    // CDFTR
@@ -1253,14 +1252,7 @@ get_irop(IROp op)
          case Iop_D64toF128:
          case Iop_D128toF32:
          case Iop_D128toF64:
-         case Iop_D128toF128: {
-            /* These IROps require the Perform Floating Point Operation
-               facility */
-            rc = system(S390X_FEATURES " s390x-pfpo");
-            // s390x_features returns 1 if feature does not exist
-            rc /= 256;
-            if (rc != 0) return NULL;
-         }
+         case Iop_D128toF128:
          break;
          /* Other */
          default:
diff --git a/none/tests/s390x/pfpo.vgtest b/none/tests/s390x/pfpo.vgtest
index 0f1f5b9c41..31d43c2856 100644
--- a/none/tests/s390x/pfpo.vgtest
+++ b/none/tests/s390x/pfpo.vgtest
@@ -1,2 +1 @@
 prog: pfpo
-prereq: test -e pfpo && ../../../tests/s390x_features s390x-pfpo
diff --git a/tests/s390x_features.c b/tests/s390x_features.c
index dc91ab549e..f9aa966404 100644
--- a/tests/s390x_features.c
+++ b/tests/s390x_features.c
@@ -231,8 +231,6 @@ static int go(char *feature, char *cpu)
       match = facilities[0] & FAC_BIT(0);
    } else if (strcmp(feature, "s390x-exrl") == 0 ) {
       match = facilities[0] & FAC_BIT(35);
-   } else if (strcmp(feature, "s390x-pfpo") == 0 ) {
-      match = facilities[0] & FAC_BIT(44);
    } else if (strcmp(feature, "s390x-vx") == 0 ) {
       /* VX needs kernel support; thus check the appropriate HWCAP bit. */
       match = GET_HWCAP() & 0x800;