i386.h (CC_REGNO): Remove FPSR_REGS.

	* config/i386/i386.h (CC_REGNO): Remove FPSR_REGS.
	* config/i386/i386.c (ix86_fixed_condition_code_regs): Use
	INVALID_REGNUM instead of FPSR_REG.
	(ix86_md_asm_adjust): Do not clobber FPSR_REG.
	* config/i386/i386.md: Update comment of FP compares.
	(fldenv): Do not clobber FPSR_REG.

From-SVN: r264694

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 7c5e78b..58a30d0 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2018-09-28  Uros Bizjak  <ubizjak@gmail.com>
+
+       * config/i386/i386.h (CC_REGNO): Remove FPSR_REGS.
+       * config/i386/i386.c (ix86_fixed_condition_code_regs): Use
+       INVALID_REGNUM instead of FPSR_REG.
+       (ix86_md_asm_adjust): Do not clobber FPSR_REG.
+       * config/i386/i386.md: Update comment of FP compares.
+       (fldenv): Do not clobber FPSR_REG.
+
 2018-09-28  Richard Biener  <rguenther@suse.de>
 
        * tree.h (BLOCK_ORIGIN): New.

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 4f64e67..8018f31 100644 (file)
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -21969,7 +21969,7 @@ static bool
 ix86_fixed_condition_code_regs (unsigned int *p1, unsigned int *p2)
 {
   *p1 = FLAGS_REG;
-  *p2 = FPSR_REG;
+  *p2 = INVALID_REGNUM;
   return true;
 }
 
@@ -43656,9 +43656,6 @@ ix86_md_asm_adjust (vec<rtx> &outputs, vec<rtx> &/*inputs*/,
                    vec<const char *> &constraints,
                    vec<rtx> &clobbers, HARD_REG_SET &clobbered_regs)
 {
-  clobbers.safe_push (gen_rtx_REG (CCFPmode, FPSR_REG));
-  SET_HARD_REG_BIT (clobbered_regs, FPSR_REG);
-
   bool saw_asm_flag = false;
 
   start_sequence ();

diff --git a/gcc/config/i386/i386.h b/gcc/config/i386/i386.h
index 0b0e2ed..6feb671 100644 (file)
--- a/gcc/config/i386/i386.h
+++ b/gcc/config/i386/i386.h
@@ -1501,7 +1501,7 @@ enum reg_class
 #define MMX_REGNO_P(N) IN_RANGE ((N), FIRST_MMX_REG, LAST_MMX_REG)
 
 #define CC_REG_P(X) (REG_P (X) && CC_REGNO_P (REGNO (X)))
-#define CC_REGNO_P(X) ((X) == FLAGS_REG || (X) == FPSR_REG)
+#define CC_REGNO_P(X) ((X) == FLAGS_REG)
 
 #define MOD4_SSE_REG_P(X) (REG_P (X) && MOD4_SSE_REGNO_P (REGNO (X)))
 #define MOD4_SSE_REGNO_P(N) ((N) == XMM0_REG  \

diff --git a/gcc/config/i386/i386.md b/gcc/config/i386/i386.md
index 2b189c8..9194751 100644 (file)
--- a/gcc/config/i386/i386.md
+++ b/gcc/config/i386/i386.md
@@ -1463,10 +1463,10 @@
 
 
 ;; FP compares, step 1:
-;; Set the FP condition codes.
+;; Set the FP condition codes and move fpsr to ax.
 
-;; We may not use "#" to split and emit these, since the REG_DEAD notes
-;; used to manage the reg stack popping would not be preserved.
+;; We may not use "#" to split and emit these
+;; due to reg-stack pops killing fpsr.
 
 (define_insn "*cmp<mode>_0_i387"
   [(set (match_operand:HI 0 "register_operand" "=a")
@@ -1649,19 +1649,7 @@
    (set_attr "fp_int_src" "true")
    (set_attr "mode" "<SWI24:MODE>")])
 
-;; FP compares, step 2
-;; Move the fpsw to ax.
-
-(define_insn "x86_fnstsw_1"
-  [(set (match_operand:HI 0 "register_operand" "=a")
-       (unspec:HI [(reg:CCFP FPSR_REG)] UNSPEC_FNSTSW))]
-  "TARGET_80387"
-  "fnstsw\t%0"
-  [(set_attr "length" "2")
-   (set_attr "mode" "SI")
-   (set_attr "unit" "i387")])
-
-;; FP compares, step 3
+;; FP compares, step 2:
 ;; Get ax into flags, general case.
 
 (define_insn "x86_sahf_1"
@@ -1683,7 +1671,7 @@
    (set_attr "bdver1_decode" "direct")
    (set_attr "mode" "SI")])
 
-;; Pentium Pro can do steps 1 through 3 in one go.
+;; Pentium Pro can do both steps in one go.
 ;; (these instructions set flags directly)
 
 (define_subst_attr "unord" "unord_subst" "" "u")
@@ -15158,6 +15146,15 @@
    }
 })
 
+(define_insn "x86_fnstsw_1"
+  [(set (match_operand:HI 0 "register_operand" "=a")
+       (unspec:HI [(reg:CCFP FPSR_REG)] UNSPEC_FNSTSW))]
+  "TARGET_80387"
+  "fnstsw\t%0"
+  [(set_attr "length" "2")
+   (set_attr "mode" "SI")
+   (set_attr "unit" "i387")])
+
 (define_insn "fpremxf4_i387"
   [(set (match_operand:XF 0 "register_operand" "=f")
        (unspec:XF [(match_operand:XF 2 "register_operand" "0")
@@ -19606,7 +19603,6 @@
 (define_insn "fldenv"
   [(unspec_volatile [(match_operand:BLK 0 "memory_operand" "m")]
                    UNSPECV_FLDENV)
-   (clobber (reg:CCFP FPSR_REG))
    (clobber (reg:XF ST0_REG))
    (clobber (reg:XF ST1_REG))
    (clobber (reg:XF ST2_REG))